I have the low floor hump without the cutout, so spaced is an issue with my 5 speed. The 5 speed is longer and taller in the rear than the original 3 speed box. Either style mount won't work with the stock rear cross member. The stock one sits 2 or 3 inches above the bottom lip of the frame in the center where the mount bolts. I need it just about level with the bottom of the frame. C channel bolted to the bottom of the frame will be good. I will make a plate to put on top of the frame for extra support but I don't think it needs it.

 

I think you pretty much have to cut the floor and get a 4 speed cover to use an M5R2. I was able to mount mine from the bottom that way. I know you said you mounted yours while putting the engine in, but what if you want to get it back out?

The bigger issue is that if you mount the rear so low (even with the frame), you'll end up with a bad driveline angle. The transmission should sit at an equal/opposite angle to the rear diff. About 5-7 degrees off from the driveshaft. Under load they will tilt and the driveshaft will end up in a relatively straight line between them. Maybe this doesn't matter as much I think though. Does anybody else have a little more knowledge on this?

 

BTW, here's how mine ended up sitting:

 

Looks great! Once I get back on my project I will have to make sure I didn't miscalculate! About the time I was ready to deal with the trans mount I was rebuilding the house I bought and getting ready to move. The poor truck has been on the back burner since spring.

 

This looks like a pretty straight forward swap if you have the tall hump. Thanks for the picture! BTW, what are you doing about your driveshaft? Is there a swap that will work or do you have to go custom?

 

I bought the slip yoke for it and am going to try shortening the driveshaft myself. There are many tutorials online. I'll probably bring it in to a shop to get balanced once I get it to the right length.

If I mess that up somehow, I'll take a trip to the junk yard to find a front section that's the right length.

 

I hadn't read post #32 earlier. If I can keep the low floor, which is preferred, and I need to get the trans back out, I can either pull engine(not preferred), or I can pull a couple cab mount bolts and lift the cab slightly. I don't need much room to get it out, the cross-member under the trans bell housing is close, but not impossible.
As far as driveshaft and rear end angles, I will be sure I line everything up correctly. I have the CV front end in my truck so the engine isn't exactly where it was positioned with the stock frame supports. I had to make engine mounts and was able to set things how I liked them.
For the driveshaft angle, I think the main thing is that the transmission output shaft and the pinion shaft need to be parallel with each other. A small driveshaft angle is needed to allow the U-joints to function correctly, you don't really want the shaft straight because the needle bearings in the U-joint caps won't really rotate for one thing. They will wear quicker that way.

 

Oh, that changes things then. Didn't realize you had swapped out the suspension.

I finished installing the clutch hydraulics on mine yesterday and everything went smoothly. The best advice I found on it was to bench bleed the master with the line already attached. It won't leak out because of the quick connect. Nothing special required, just put it in a vise tilted slightly down and keep pumping until there are no more bubbles and you can only push in about 1/8". It took about 30 min. Use a screwdriver or something instead of the pushrod, because it locks in and becomes a pain to install that way. Then install it in the truck, connect the line to the slave and gravity bleed the slave. That's all it took-- no pumping and cracking the bleeder for an hour or anything. Just verify that the throwout moves about 1/2" when you're done.

 

Thanks for the info on the clutch! I will have to do that as well myself. I haven't fooled with hydraulic clutches much so I wasn't too sure how bleeding was going to work. I haven't mounted the master yet, my plan is to mount it to the firewall and use the stock pedal. I will have to modify the arm on the clutch shaft but it looked like it will be fairly simple to accomplish. If I have enough clutch pedal travel to be able to drop my pedal a bit. It is real high off the floor in stock position. Hoping with a shorter throw I can have pedal closer to floor when it isn't being pushed. I'm thinking I can just reposition the pedal bump stop under the dash so it can't come up so much. Not sure yet if it will work that way but that was my thought on it.

 

If you want the pedal lower you'll need to make the arm on the pedal longer so that you'll get full travel of the pushrod. The trade-off is that you'll have to push harder on the pedal. I modified the arm just to change the direction and ended up with the exact same pedal height as stock.

 

I will have to take a look at it. I bought a house mid project and it threw a wrench in my truck plans! I started fooling with the clutch and brake stuff and then moved so I forgot where I was at. If I remember right it seems like moving the arm like you said will have to happen. Its ok if I can't lower the pedal but I'd like to a little bit. Even lowering it an inch or so would be an improvement if I can keep good throw on the arm under the dash.

 

As I stated above in post #8, I have a rebuilt T5 from a 1985 Mustang.

 

I finished the M5R2 swap on my 66 with the 240 today. Shifts great, I'm really happy with the clutch feel. I think I can shorten the pushrod a little more, because it has way more travel than necessary. The clutch doesn't engage until almost the top of the pedal travel.

The only thing is that it has a fairly loud whine under load. Sounds like the 3 speed did in reverse. Not super loud, but enough to be annoying. I'm hoping that this is normal and that it's quieter when I get the insulation and new vinyl floor down. It's a used transmission and I'm using regular Valvoline Dex/Merc ATF.

 

I finally settled on a T5 from a '93 mustang. Looking forward to doing this swap after a few other projects. Anyone have any T5/66 F100 specific advice?

 

This guy swapped a T5 into a dent, might have something useful for you.