Just curious are you just trying to lower the fuel milage or what is the reason behind the 4 inch lift on a 2x. I doubt if there is a lift for the twin I beams you might try the pre runner crowd, they did some amazing things with the suspentions on the 2x's.

 

For a 2wd, the bracketry for a F150 will work, springs however will be a whole different issue. Skyjacker does make 2wd intended lift kits though. You are still looking at 500+ for a proper setup though.
Your ideas for making your own stuff, please, PLEASE take them and throw them out the window.

 

The two wheel drive twin I beam and the 4x4 twin traction beam both have the same issues with ride height.

Taller springs raises the truck up, and gets the alignment so far out of whack there is not enough adjustment to get it back within specification.

No big deal?

Well you are talking your life as well as anyone riding with you or meeting you on the highway when it breaks.
Only way to do a front end lift is with the correct lift kit if you want a safe vehicle.

 

2" 80-98 Ford F250 add-a-leaf Leveling Lift Kit - Top Gun Customz
i know its not 4 inch but is this for the TTB? would it throw alignment way off and not possible to get back to spec?

 

With my snow plow I have air bags on my front axle.
When the IFS front axle was still under my truck I was over at Ford for an alignment one Saturday.

While it was on the rack, we played with air pressure in the bags.

10 PSI raised the the plow bracket 1".
With the biggest offset bushing Ford had, 1" was the biggest height increase my IFS axle could take and still be able to get back in alignment.

Also if you drive the truck straight forward on a level surface an stop when you look at the front tires they must be either vertical or slightly / \ looking.
If they sit like this \ / you are beyond what the alignment adjustments can handle.

Without dropping the center mounting points, more than an inch height increase makes the tires sit like this \ /.
The higher you go, the worse it gets.

The center drop brackets are why IFS axle lifts are so expensive and hard to install.
Lots more work than just adding springs on a straight axle.

Since the 80's model 250's had IFS front axles, and those add a leafs will fit, they can be added to the 250 front spring pack.
But my guess is they will also make it so far out of alignment that the adjustments will not be able to get it back in alignment with them installed.
So the steering and tire wear will be less than desireable.

If you stop and think about the cost of mud tires, you can't wear more than one set out before the cost of the right lift kit is not really that expensive.
And if you think about it a little longer, that Dana 60 axle that costs 1500 is cheaper than two sets of mud tires, so again it is not that expensive.

When I had the IFS under my truck, tires were 800 a set.
Two years and they were shot.
With the 60 under there, the same tires are now starting on the fourth year, and still have decent but not great tread left.
So in four years, the 60 has already returned 1/2 the purchase price in tire wear savings alone.
Add in the ball joint and tie rod replacement costs every year with the 44 that was under there originally, axle is paid for and the rebuild and traction lock I added is also paid for in only 4 years.

So that was an upgrade that is now putting money in my pocket every year.
When I did the upgrade, the axle, parts I replaced and added to the axle and the parts I replaced when I installed it under my truck came to 3000 dollars total cost.
Paid for in four years is a rather good return on that investment.

If you don't use your truck as hard as I do mine, it will take longer, but it will pay for itself in the long run if you keep your truck.