Grant Tuff Wheel in my 67 Dart...
I put an original tuff wheel on my 70 duster and used the spacer. Prior to that I had a grant wheel (not the tuff one) and my knees hit the wheel and of course the turn signal interfered. I am 6'2" tall so my seat is back fully. I was very satisfied with the tuff wheel spacer as it put the wheel in the right place for me.
In a recent mopar action Ehrenberg goes into detail on this and it is a good read. He actually shortened a spacer to make it work for him.