I just installed my new wheels & figured I'd post the information here for anyone else who's thinking about 18's on a 1971 Skylark. The car is not on the road so I can't road test but according to the website I ordered them from (carid) they are guaranteed to fit. They look like they fit with no potential rubbing but once I finally get the car down the road I'll know for sure. Wheels are Vision 143's, 18 x 8.5, -6 offset in the front with General G-Max RS 245/45ZR18 & 18 x 9.5, 0 offset with G-Max 275/40ZR18's. We're moving within the next 6 weeks so I don't know when I'll have time to change out the springs but the plan is to drop it at least an inch if not more depending on what I decide to do with the suspension. Excuse the dust, rust & lack of interior but here you go!
