a kit s/c is easier over all in the end. no fabbing for the most part. there isnt that much room in a 4.3 truck engine compartment.

A t-25 is rather small for a 4.3 unless he does twins, then that really makes things really complicated. A 4.3 already makes 200 hp, and a t25 can support upto 250ish-260ish.

if he was gonna go turbo, id just get an STS rear mount turbo kit