the register i was referring to was the hub area where the wheel centers inside the stud area. not sure where you got the 3.25 dimension ? all mopar wheel registers were 2.800 on discs or drums for many, many years. that's why ford wheels won't fit on mopars. although the bolt pattern is the same, their wheel register was a tiny bit small at 2.750 id. the one thing you may need to check is possible caliper interference on your front discs. if a 15" minivan wheel doesn't fit by rubbing your calipers, you may need to source a 16" wheel from a 94 up concorde, intrepid, or LHS. they also have the 4 1/2" bolt pattern and 2.820 wheel id. if i get a chance, i'll bolt up a doughnut to a spindle and caliper assembly i have here and take a pic or two.