AJ - I swapped a bunch of parts around on 70's Ferds. I learned that most of what they told me about stuff not working on the trucks was bull. Bear in mind, I only dealt with 302's and 351W motors. I put a 302 from a thunderbird, bellhousing from a station wagon, transmission and transfer from a 76 F-150 and axles from a 74 Bronco into a Willys.
The only item I had to have fabricated was the front driveshaft. Everything else bolted together.
One of the biggest problems was the input shaft on the 435 length. Big blocks and 300 I6's used the same input shaft. 302 and 351W used a deeper bell housing and a longer input shaft. Took a technician to tell where to look for the right length input shaft. If he hadn't come in for a drink of water and heard us, I might have abandoned the project.
We also bought a 64 unibody already built with a 302 and a C6/205. Even with my teenage son driving it, I never had to work on it.
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