Joe:

I installed a set of Ronal R28's (16X7.5 w/ 35mm offset) on my 90.  Am running 205X55X16 tires.  Purchased 10mm hubcentric spacers for all four wheels from Ronal as well.  I did not have clearance problems with my rears at all but installed spacers just to be even all the way around.  Without spacers I had a conflict with the control arm on the fronts.  Have a picture of this spot posted on my website (see link below).  Go to suspension, wheels & tires.  I've also got an excel spreadsheet out there that allows you to enter the desired tire size and will show you the rolling diameter difference from stock for that tire.

With the spacers, make sure that you still have at least 8 threads of purchase with your lugs.  I had to go with longer bolts in front and longer studs in rear.  Empi was the manufacturer of the studs.

I remember having to be careful about the front wheels and the need for a larger than normal center bore, something like 60mm to accomodate the large vanagon front hub.  Ben T has excellent information posted on his site re this topic.

Brent