What all will I need to run a 302 in my 70 F100, I am doing a frame off and everything is apart right now, It currently has a 360, will I have to swap the frame mounts? what else will need to be changed, I already have a trans. If I go with the 302 I will run Mustang EFI on it. I am looking at my options. I will either use a EFI 5.0/ 429 or build a 390. I have acess to one of each so that is not a problem.

 

The 390 will bolt right in. If your truck is a 2 wheel drive, if you want to install the 302 correctly, you have to use the frame mounts from a 69 to 79, 302 two wheel drive truck. Some say the frame mounts from a 351M/400 will also work for the 302, but I can't verify this. Your crossmember should work with the original trans mount, but you may have to drill new holes in the frame, depending on what trans you use.
I'm kind of partial to the 302 idea for many reasons, including parts availability and better mileage then the other two engines you mentioned.
If you end up doing the EFI 5.0, I would like to get some info from you. I also am doing a frame off on a 70. I rebuilt the original 302, but am using an Edelbrock carb, manifold, cam and heads. I would rather have EFI, but have never done it before. I installed a C5 automatic in place of the 3-speed column shift. I'm under the impression the mileage should be a little better because of the torque converter lock-up feature of the C5. I wouldn't mind adding overdrive, but I'm not sure of my options. I would appreciate any advise concerning the overdrive options. I have Mustang T5's in two of my other trucks, but I want this one to shift for itself. I know the AOD can be built to hold up, but I don't like them for a number of reasons.

 

Im still looking at my options, I will have a workable 5.0 out of my 87 Mustang as soon as the new motor gets finished. I have a couple spare injection setups and a Speed density computer. The only thing I will need is a AOD. Any way you can install a 302 on the FE frame mounts? The truck is a 2wd if that matters? I just installed the disc brakes up front and have the cab off. So I have awhile before the motor goes in.

 

Yes, a 302 will bolt right to the FE frame mounts. I have done it both ways. If you use the FE frame mounts, the engine sits up higher then stock, and about 2 1/2 to 3 inches further toward the front of the truck. The biggest problems I had using the FE frame mounts, was trying to use headers, and finding a driveshaft that fit. I used one from a 79 F100 with a manual transmission. I had to have one of the tubes on the passenger side cut off, and a new one bent a little different and welded back on. Ford made the small block engine stands for a reason I have to think. I'm sure you get better weight distribution and a lower center of gravity with the engine in the proper place. Also, if I add power steering to the truck with the FE stands, I'll have to have the header redone on the drivers side as well, to make room for the larger gearbox. You can do it either way. I'm just thinking, that if you're taking the time to do a frame off restification, you might as well take the time to go to the junkyard and unbolt a set of small block stands for your truck. They're all over the place, and I only paid 25 bucks for mine.