http://www.welderseries.com/
Got a set of LS-mounts to put a 4.8 in my '47 IH (sitting on a 65 C-10 frame) and they were awesome. I used my truck mounts, had to trim them a little but did retain the truck mounts, they costs 60.00 for the set and worked and looked great! A+ service also.
Purchased a Painless 4.8/5.3/6.0 harness and it was the best wiring harness I have ever installed! Great instructions, took about two hours to complete!
Plus, since I got the harness, they flash te Vats and EGR stuff out for free!
TWO GREAT COMPANIES TO WORK WITH. A+ Money well spent!