I did an e4od swap on my '86 f350 a while back and I can tell you it's not as bad as a lot of people will make it sound. I found a complete donor truck in a junkyard (90 f350 cab& chassis), pulled the trans and every part that was different as well as all the wiring and trans control computer. The hardest part about the whole thing was trimming down the harness from the '90 to only have what I needed to work the transmission and making the holes in the frame for the trans cross member braces to bolt down. My work doesn't exactly look factory but it is professional with all factory parts and everything plugs in with original connectors. I could remove the e4od and put the c6 back in and the only visible difference would be the extra holes in the top of the frame rail. Had I found a good zf5 for a decent price I probably would have gone that route but I don't regret the e4od or the experience I gained from the work I did. Honestly I am pretty proud of the fact that it's been together and working for about 2.5 years now with not a single issue.