I recently put on Mercedes CLKJ 16" wheels in my '89 automatic.  There
is an abundance of information on the internet and it took me quite a
while to find the information that I was looking for.  Whether you
want to upgrade to 15", 16"', 17", or even larger wheels, make sure
you find the right combination if wheels and tires for your particular
Vanagon.  I ended up opting to go with the CLKs and Hankook Ventus V4
225/55/16 99XL .  I did use spacers and the hardware from http://t3technique.com/
   I know have to get the Wolfsburg caps that he mills to fit the
wheels.  I like the look and the cornering is better.  The ride is a
bit rougher than the 195 R14s that I had.  Here is a picture; http://www.kookymathteacher.com/CLKs.JPG

-Jamie Auch