I started this project AFTER just installing a brand new Chevy 454 HO 425 HP crate motor in the truck. I mistakenly thought that the hot rod motor would have great torque and pulling power. I did not see the torque curve on it, just the 520# figure. A tow motor needs to make the torque down low (around 2000 rpm) and the HO motor makes it in the mid 3000 range, too high to be useful. I sold it off after already buying a new (but damaged) Duramax motor and Allison trans off ebay. I had wanted to take more time to engineer the install, but as the 454 sold the first day the ad came out, and the guy had to have it on a boat the next morning, I had no choice. I thought the project would take about 6 months. The install is already exactly one year old to the day (as of 8/29/04), and VERY FAR from usable. I had researched the Diesel Page and found a fellow in Montana had done this swap into an 89 Chevy 1/2 ton pickup, and it took him two years. His install is a wonder of initiative and creativity, and he has done a more than first class job of engineering, documenting, and performing the work. There are substantial differences in the frame configuration on my 1-ton 86 versus his truck.
I believe he also may have set his motor in a bit higher. So here goes the story from before I even owned the Duramax motor and Allison trans: