60" wide .032/.040 for roof

Ok folks,Newbie here.This is my first real post ( woo hoo!).
I needs some input on 60 wide sheet(alum.) I work in in steel whse.,but we don't stock ,or can get .032/.040x 60x120. although we do have .063 type 3003,but I want to avoid useing that heavy of material. I don't think it will cooperate with me that well.I am planning on scooting the old Impala over & startin my project this winter/spring as a 5x10.Any suggestions on the sheet supplier? 

