yeah, you'd have to relocate the leafs inside the frame, or link/coil-over the rear (and relocate fuel tank) to get much narrower, depending on how wide your wheels/tires were.

Seems a lot of the RGV truck guys do that.

 

If he Just wants the same size rim with a deeper dish wheel he can have it narrowed with out all the other work.

I think the standard off set is around 5 inches deep...Deppending on the rim's out there he may be able to get one thats only 3 inches deep and have the rear narrowed 2 inches per side so that they look deep.

 

this is how you would narrow it using a line up bar. I had to make the attachments for the 14 bolt pictured.