welp my 87 coupe came with 15" weld wheels on it front and back...now im curious on how to figure out exactly what size,width,backspacing, etc the wheels are...how can i figure this info out? the tires up front are 225/50/15 and the tires out back are 215/60/15....im trying to figure out the info on the rims so i can get a nice set of tires out back so i can have some traction.....i did measure inside the rims from center of rim to the end of the rims and in the front it was 6 inchs and in the back it was 5 inches....does that info sound right?