[biketopia]

Are you dead set on using the stock ECM and harness? Are you doing any motor upgrades before transplant, or maybe after? Have you looked into doing a holley terminator x max? You get a new harness, engine and transmission management, self learning, and the ability to lap top tune everything, without additional HP tuners or EFILive credits. You also get a handheld to monitor engine paramters, or you can get a holley dash to see everything and people make a mount for them for those trucks. If you're leaving it mostly stock then stock harness and ECM are ok, but if you like to tinker and want to learn the holley the system, it's a very attractive choice. I'm not super familiar with the square body's, but I think you can actually keep the stock truck pan. There's block off's on Ebay for the EGR. Are you going though the 4l60, they can be made to last, if you're towing with it I'd suggest a huge cooler at a minimum, and maybe a build as well. I would also open up the engine and do a high lift truck cam to bring the torque in down low where you want it. A high lift truck cam from Summit, or Texas speed, isn't a massive cam, it's just their marketing. I put a low lift texas speed truck cam in my 08 and wish I went with the high lift version as it moves the torque curve down lower.