check out the topics stickied here in this section. There are many vendors that make a nice conversion harness. I just used one of NelsonPerformance.com custom harnesses and it was a piece of cake to install and fired right up. The current transmission you have is fine, you'll just need a crankshaft spacer, flat flexplate and longer bolts. I get them from crateenginedepot.com . Check out Schoenfeldheaders.com , they are a site sponsor and are now making headers for the OBS trucks and retail them for $250 right now.