Aloha Rudy,
 
My memory is a little clouded, but when I = bought my Wolfsburg new back in 1989, I asked the salesman what the difference was = between the Carat and Wolfsburg.  I had owned two previous VW vans, so was = familiar with the Wolfsburg edition, but had never heard of the Carat model.  The salesman did not know, but found a technician who said the difference was in the = stock sound system.  The Wolfsburg had such and such a sound system, and = the Carat had some other system.  I don't really know if this = was accurate.  
 
The operating instruction pamphlet for my van identifies the radio as a Heidelberg 5 Stereo = CR.  It has the regular four speakers as other = Vanagons, and a fifth 5.25" dual voice coil speaker in a sound box in = the side panel behind the drivers seat (acts as a woofer). 
 
The radio deck has sixteen wires in its = harness.  The Bentley shows a system with an = amplified fifth speaker.  Perhaps this is why I = discovered six wires going to the soundbox when I completely took out my interior to add = sound insulation two years ago.
 
Unfortunately, I don't remember what = system was supposed to be in the Carat, and don't know if it is an upgrade = from the Wolfsburg's. 
 
It's been over eleven years since that conversation, so I can't recall if any other differences were = mentioned.  From my observations, the Wolfies and the Carats look pretty much the = same, although I haven't seen any Carats with the gray diagonal pinstripe upholstery.  I've also come upon some Wolfies and Carats that = do not have the leather covered steering wheel that came stock on = mine. 
 
By the way, my van has just turned = 110,000 miles.  It's been very dependable and a pleasure to own.  = Heads were redone at 80,000 miles, body repainted at 98,000 miles.  = Brakes, numerous rubber trim pieces, hoses, carpets, etc. were replaced as = needed.  Speakers were replaced two years ago with 5.5" Blaupunkts in the = doors and 4" Blaupunkts in the rear.  Couldn't find a 5.25" dual voice coil fifth speaker, so rebuilt it. 
 
The van is always filled with windsurfers, = surfboards, kayaks, mountain bikes, camping gear, and occasionally over thirty scuba = tanks and other dive gear, but is still rust free.  Kind of surprising, considering Hawaii's salty tradewinds.  The upholstery has held up well against my two young kids and family dog.
 
Just wish the motor had more = pickup.
 
I really can't judge the '89 you're looking = at, but I have absolutely no regrets of having purchased mine, and hope to = keep it for a long time more.
 
Aloha,
 
Alan
Honolulu, Hawaii