I have always thought the old Mustang II stuff worked pretty well. You can buy kits that weld up to your exisitng frame using Mustang II front end parts. Some Mustang II's came with 302's and 5 lug front wheels. Although I believe that you can get rotors drilled with any pattern you like. You may have already though about this, but I think the airbags are the way to go for the suspension. I have always stayed away form the volaire and camaro stuff as it isn't ford stuff and I am not a big fan of chopping a frame into two pieces and then welding it back together. Should be a fun project.