[cdub2010]

I did the same swap in my '77 k2500 with 5.3 4l80e np241. I used dirty dingo sliders, psi harness & ecu. I reused a stock front shaft from a 3/4 ton suburban. I had the rear shaft made new with 1350 joints on both ends. There is no way I would ever use a th400 instead of a 4l80e, the overdive is so much worth it. My truck can cruise at 80 on the highway very smooth. It was money well spent. My stock 5.3 with 31" tires and 4:11 gears is more than enough power for my needs.

You will be limited in how far forward you can go with the engine as the engine crossmember will need to be swapped out or trimmed for the oil pan clearance. I cut mine and had no issues. Dont worry about max power from the 6.0 its fine in stock form. Id get your truck running and driving before you chase all hp's. Dont cheap out, do it right, use good wiring, check, clean or replace all your grounds. I used 87+ tbi tank with ep 381 pump stainless fuel line plumbing. I ditched the second tank for simplicity. Full stainless exhaust, I will ditch the cheap stainless headers for some hooker cast exhaust manifolds, in the spring. The chineese stainless headers have rusted real bad. Been 5 years of use, I love the truck, Ill never use a sbc or carb again. Mine wasn't a cheap swap but its reliable and fun to drive.

Good luck with your health and your project. Im one year out from brain and heart surgery. Im finally just starting to feel like finishing a few projects that have been sitting for a while as well.