l have been asking info on putting fx45 20" wheels on a g35 coupe and everyone is telling me that the bolt pattern matches but the offset doesnt. What does offset mean? Does this refer to the width of the rim and everyone is stating that it will stick out of the finderwell?

 

Offset is how far in or out the rim will sit.

http://www.tirerack.com/wheels/tech/offset.jsp

 

You can also take a look at this:

http://www.rsracing.com/tech-wheel.html

 

read the forums here and do a search!!
https://g35driver.com/forums/wheels-tires/41185-need-info-how-understand-offset-lip-size.html