That link you posted for the oem replacement pump, is of oe spec, meaning 90lph of so. And yes, it's for 1990+ vehicles that use the fdm, instead of the tank selector on the frame.
If you want a badass pump, for the rear anyway, and want to get rid of the tank selector on frame, upgrade the rear tank to a f26, and use this...
HFP 255LPH Fuel Pump Assembly *Rear Tank* Ford F150 1990 - 1996

 

It would be somewhat problematic and expensive to go this route... as the F26e is made up to 1989 trucks...not 1990+.

Don't know if a 1990 or later hanger (different type pump, would need new hanger)would work on this tank, or what other mods would need to be done to get it to fit and work correctly... as the tank is much deeper also.

I could use the F26e with my current hanger, add an aftermarket high pressure in-tank pump and lengthen the shaft on the sending unit to accommodate the deeper tank.

EDIT:

Ok, after a little more research it looks like this tank also works on up to 1997 trucks, so the 1990's style hanger should fit, but again, that's over $100 for a new hanger by itself... this is getting expensive, over $450 for tank + hanger + pump...

 

You need to get a little more creative...
Junkyard hanger is like $12.
You don't NEED to upgrade the tank, it was a suggestion. But if you need a new tank anyway, you might as well upgrade.
The fdm eliminates the need for the frame rail tank selector, so if you're upgrading anyway, then the cost of the newer lines isn't a big deal. Again, go to junkyard. The newer fuel lines are stainless... And cheap.

If you don't care about dual tanks, or want to run a bigger pump with your frame rail tank selector, just buy a walbro 255, they are under 100 on eBay. Put another fuel filter where the frame mounted high pressure pump was, that's what I've done.

 

I originally planned to use the Walbro 255, but just so everyone knows... ONLY buy them from Walbro!
The market, including parts dealers, are flooded with counterfeit pumps that prematurely fail.
There are many, many posts about this and articles on the internet... it is so bad that even Walbro has posted this on their website:

http://walbrofuelpumps.com/media/fav...lt/favicon.ico

I may just replace existing low pressure in-tank pump with Walbro 255 in rear tank, replace supply fuel line with later stainless and run 1 tank for now... then add the tank selector valve and replace 2nd tank low pressure in-tank pump with another Walbro 255 later.... I have other parts needed for the truck and limited funds

 

Ive the older 3 pump setup on my truck, for a while there both in tank pumps had stopped working and the pump mounted on the chassis was doing all the work, truck still ran ok except when really hot it would carry on a bit, but handy to know that if you do have an in tank pump fail the truck will still get you some place where you can fix it.

 

Curious what you used for fuel line connectors? I should be ok with the OE return line, but not sure what will be needed with the replacement 1990+ donor stainless supply line, as far as available fuel line connectors?

 

Seconded. Many, many people with dual tanks run it until it bucks then flip the switch and hope to make it until payday and the pumps last just fine.

Should be as easy as a switch to connect both fuel pump power wires together at the switch.

 

If both pumps were connected and both running at the same time, would that not cause issues in there situation where one tank ran out of gas but the pump is still pumping?

 

My truck is a 90, and wouldn't need alteration.
The biggest difference between the 89- trucks, and 90+, would be the electrical connection, not the fuel line connection. I'm pretty sure they changed early 90s, but I don't know the year.
The fuel connectors are all the same. 3/8 for pressure and 5/16 for return. But if you need to, you can use high pressure fuel hose to make connections if you use the high pressure clamps along with it.

 

The mod to run both pumps at the same time requires you to pay attention to fuel level. Wether you're low on fuel and running both pumps, or if one tank is full and one is partial, so you don't over fill one of them. You gotta have a little common sense and pay attention when modifying your vehicles.

 

Not sure if I understand your statement?

I would assume that use of the original fuel pump relay/computer connection to the original fuel selector switch (rocker switch) is used.

Are you talking about using an in-tank pump AND an exterior HP pump?

If so, if you ran out of gas, the truck would immediately stop running, thus, taking out all pumps.

If you are talking about both in-tank pumps, only one at a time can be used (switch valve) and same, if tank runs out of fuel, truck stops running.

You may be referring to something else, but I don't see this any different than how the truck is originally?

 

When you say electrical connection being different, are you referring to the valve switch? If so, would'nt that just be a matter of splicing in an after market 6 port switch valve for dual tank use? Are there other differences in the system that need attention?

Just a little confused with the 2 main type of fuel line connectors used... on my 1989 truck, it uses the type called 'Push Connect' fitting that use the 'Hairpin Clip' that you remove before unistalling and replace when installing.
But when I search for replacements from Dorman or other sites, mostly all I can find are the other type, which are called 'Quick Connect' fittings, which don't have the Hairpin Clip... not sure if these two types are compatible, as one place the 'Push Connect' fittings are used is on the Dual Function Reservoir, which is plastic. The other type fitting, the 'Quick Connect' fitting, are advertised as "metal to nylon connection".

I have messaged the Dorman site a couple times awhile ago and have yet to get a reply.

If these 2 types of fittings were compatible, that would be great, as the 'Quick Connect' fittings are much cheaper than the ones I have already!

Another question is PSI rating of these connectors, as I have also not been able to find this information... I seen somewhere that the existing nylon line is rated to be able to handle 60 psi, which I would think not high enough for the Walbro pumps that can reach pressures higher than that.

If possible, I think the easiest/fastest install would be to be able to use nylon fuel line, (new install if need higher pressure line) and be able to use the 'Quick Connect' fittings, as long as it is SAFE, which is the first priority.

 

The lightning guys run both in tank pumps at the same time to supply fuel to their higher hp engines, that's what rj1983 mentioned, and what I quoted.
Both in tank pumps CAN run at the same time when using 90+ fdm and pumps.

 

Even though the nylon line is possibly rated for only 60psi, and the walbro pumps rated for more than that, you don't need to worry because the regulator won't let it get that high unless there's a malfunction.