Putting 96 z28 camaro rims on a 91 rs camaro?

I dont know much about cars so bare with me, i have some rims for a 1996 z28 camaro im trying to put on a 1991 rs camaro, problem is the tires are very wide so the rims cant reach the bolts on the hub i think its called. I need some spacers but i dont know which size and im not even sure if the camaro rs lug patern is the same as the z28 rims. any suggestions on what i need get to put the rims on?