I have a 1990 C1500 Phantom Dually Long Bed and am going to put 29x 18.5 out back. My question is, should I go with a LS1 or LS6? both can be built from the same block as far as I know (new to the LS1 scene). I am wanting to turbo either one I go with. Money wise, $10k for the swap and upgrading the motor because it's going to be built over a period of time. I have a stock 4.3L now and it ain't going to do jack with these tires. Im wanting atleast 450whp. Ideas?