Any one here an expert on auto wheel fitment. I bought a used set of american racing wheels that came off a 97 Mustang GT. They have a positive offset of 42, as best as I can tell, they look like they are for a front wheel drive. I have also read where a lot of guys put the 5x114.3 (Mustang) on a 5x115(Chevy) vehicle. I have a 99 Monte Carlo which I am fixing up that I would consider putting them on, but I am also looking for a mid 90s Mustang convertible to fix and sell. Have read positive annd negative about interchangability and also the use of spacers and the use of hub centric rings. My question regards older wheels from 3osome years ago, it was one size for chevy, one for ford, and one for mopars. Some even had uni lug, an elongated hole to fit all vehicles. Why so many sizes now and what is safe? also do shops rebore the bolt pattern to fit more than one vehicle? Thanks.