FE's are not "Y blocks" they are a 90 degree V like most V engines. The Y block was the tiny lifter 292/312 and other smaller displacement engine that preceded the FE. The FE was loosely based on the MEL motor, but shares nothing whatsoever with the Y block.
OK, got me there. I've got to learn to not reference two families of engines when thinking of one, or get some sleep at night so I don't think so off topic. Truth is that the FE 360 I previously ran in my 73 F100 4x4 Highboy with 4 speed got me 16 mpg just before the end. I credit the 33" tires on stock gears, careful 2bbl rebuild, and the points I just put in. Granted that was just before the tired engine politely told me it needed rebuilding. The engine only spent most of its 60K miles in the 20 y/o body pulling farm equipment and product. The Y block was in an older truck that I was thinking of.
But back to the topic at hand, and that's an IDI swap into a 70's chassis.
I'm all for it, no matter the work involved. My '77 F250 highboy with the 351m has been crying for something all oily smelling to run inside it. And with the 86 I have the 6.9 in now needing some pretty hefty body and front end work done to it, I am considering it also. Since it has a divorced 205 I just don't know if i want to retain the stock 4 speed or convert to the C6 on the back of the diesel. Either way, it will be a lot of work, but in the end it will be a custom rig which is always worth it to me. Even if I have to bust my back trying to remove the body mounts to put a minor body lift in for the engine clearance, and maybe preparation for a turbo someday.
With a welder, some steel, patience, and somewhere tin and vehicle can sit separate from each other for a while, we cam build whatever we want however we want it. If the amount of work is worth it, well that depends on what you want in the end. Just don't do any custom work half-assed and it should turn out fine. Maybe a money pit, but if it's what you want and the factory doesn't offer it, then you've definitely got a unique vehicle.
A fella I know of is working on putting a John Deere 6-466T engine in his 82 Ford F350. It promises to be a killer beast when he's done due to the fact that the engine is built to Farm Stock tractor pulling specs. It kinda has me inspired to do the same thing someday. That is, when my rich uncle gets out of the poorhouse.
