What size bags to run on 93 fullsize chevy half ton?

My buddy wants to put bags on his 1/2ton what size fits on those. I have never worked on one, always had the 1 tons to work on. We are going to put slams on it, 6,7,8's?

7s all the way around.

ditto that

Thats what I thought but figured I would double check to make sure.