I have a friend I worked with that now had his own shop. He has a 80s modle silverado 4x4 he is putting a 5.3 in for a customer. Does anyone know of a long tube header that will fit?

 

F body headers should fit

 

there are none AFAIK.

f-body headers kick out and hit the frame. all i've seen have had to be cut and rewelded.

 

Ok I think he is going to get the tsp ones due to the recent price drop as a starting point and cut and weld as needed.

 

Schoenfeld makes a header for that swap not sure if it works with 4x4.

 

Schoenfeld gmt 400 headers fit my 85 k10. Only had to make a small notch on the driver side to clear. It's kinda tight on the passenger side but doesn't rub.
The truck is stock height with the engine as far forward as the dingo mounts will allow to get the 80E in stock location. Hope this helps.