I've done this on my '84 Vanagon.  Dunno how the '90 is different, but a few 
tips from my experience which may o may not help.

+ remove the radio to help get access to the levers in the dash.
+ remove the ashtray too.
+ go slow.  Allow a whole day.
+ remember that the levers in the dash come out whole, and slide into
  little sockets inside.  Don't make the mistake of prying off the handles,
  They'll never go back on.
+ I found that pulling off the cover of the heater helped, but it's not obvious
how it comes off (and I've forgotton).  Be careful.  Go slow.  Don;t force it.

Hope it helps.
>>>"Clark M. Carr" said:
 > Greetings all.  I'm afraid I'm new to both the list and the world of busses 
     so
 > if I'm doing this the wrong way please give adjustment advise.
 > 
 > I picked up the most fun vehicle I've ever owned about two months ago: A 199
     0
 > Westfalia Camper in really nice condition.  So far it has logged 7000 miles 
     and
 > attended 4 skydiving conventions with me. Camping at the conventions was the
 > real purpose of the acquisition.
 > 
 > So OK, now winter is setting in and I'm thinking about doing some skiing.  O
     nly
 > problem is that I went to try the heat for the first time and the cable that
 > opens up the foot vents in the front is broken. This means really cold toes
 > while my face burns red.  So the dealer wants a meager $12 for the part but
 > wants $390.00 to install it. Gulp.  Being a reasonable guy, I thought I migh
     t
 > tap some of this expertise and have a go at doing it myself.
 > 
 > So, I'm looking for a recommendation of a book that will walk me through the
 > process of disassembling my dashboard and then re-constructing it again.  Se
     ems
 > like I could replace the burnt out bulbs and add a couple more lighter socke
     ts
 > to power some add ons if I don't get into too much trouble.
 > 
 > I would also be eternally grateful for any tips or tricks about the procedur
     e
 > and, if necessary, a warning about how guys who don't know what they're doin
     g
 > shouldn't be doing things like this if I'm going to end up taking all the
 > removed pieces back to the dealer with a pitiful look on my face.
 > 
 > Thanks and wish me luck,
 > 
 > Clark Carr
 > '90 Camper searching for blue sky
 > 
 > 

  --berry

Berry Kercheval :: kerch@parc.xerox.com :: Xerox Palo Alto Research Center