I modified my Kit
I put a 5. 9L in a 93 Chevy 4x4, ext cab, almost same truck, a tad shorter.
I bought a 4" kit for a Dodge, and modified the pipe with a deeper bend to miss the firewall, which is an issue you will have also. First, I ground the MIG welds off the kit, and re-positioned the joints and tacked them, then brazed the joints together now fitting a Chevy. This required reducing joint lengths, basically. Since the kit came to fit a Crew cab and required shortening anyway, it worked well for me. I also adjusted my bend over the axle to suit my needs. The serious modification was the joint up at the firewall, otherwise putting a Dodge kit on a Chevy is easy.
I also had to flatten the cab seams, because a Chevy is not designed for a 4 or 5" exhaust. I have clearance and a good exhaust.
Wayne