18x8's front 18x9.5's back 69 Bird

[av8or32]

Got a pair of new 18x8" wheels last night (coy's c-5's) w/235 40's. At first I thought they would be wide enough for the back of my firebird but after looking them over I realize I want 9.5's w5.5" b.s. and 275 40's on the rear. My ? is, will these work up front on the stock subframe? The back spacing is 4". Also, they didn't come with lugs so I was wondering what type they use. I read a post yesterday that someone measured the rear end on a firebird and it was 1" wider than a camaro. Will this grossly affect my plans or can I get by without rolling my quarter lips? I've got drums on the rear for now but I'll be upgrading to discs later. Factory discs up front and planning on upgrading to big brakes as well. I'll measure the rear end tonight to be sure.