Thanks for the add guys! I have a '77 K25 I'm working towards putting an 8.1l Vortec into that I got for a really good price. I e always been a diy guy with vehicles and built my own Megasquirt unit for my car. I didn't want to get that involved with the truck though. Hoping to stay away from HPT but they make it so tempting with the support and easy program layout. I'm sure I will have plenty of questions and concerns with setting up Tunerpro but it looks like I found a bin and XDF already to get me started.