72 gmc jimmy dual exhaust

[Sandtrap9072]

I finally got my new full length headers from hedman but now I'm wondering about running dual exhaust out the side of the quarters. I currently dump under the truck just past the rear axles. What I am wondering is do any of you guys know of a good header back kit that is easy to install? I do know how to weld but just need some help determining what kit I may need. (Ie what size tubing, proper bends so on and so forth)Headers have 3 inch collectors. Any help would be greatly appreciated.

Thanks