John took a LQ4 short block and put an LS3 top on it along with a 219/233 cam, headers, and 2400 stall. Truck is fresh out of the body shop with new rims and tires that are not going to last long.
John’s 1968 C10 6.0 4l60
James 1968 C10 6.0 6l80 Swap 
James installed a 2010 LY6 6.0 and 6l80 into his C10 last summer and brought it to FLP and myself for finishing. This year he brought it back for a BTR Stage 2 PDS cam(227/242 .614/.592 122+6) and accompanying tuning to go with his 4.10 Trailblazer SS differential. 4.10 gears and a 6l80 make the first gears just about useless as you go sideways with the tires up in smoke.