302 and 351 windsor have the same bellhousing.

302 only came in 2wd so would have to fab motor mounts if 4wd(actually doing this right now). 351 windsor didn't come in any 70's ford pickups so would also require some fabrication.

If you don't have either these it would probably be easier to get the 390 mounts and bellhousing and whatever wiring/accessories are needed.