I recently had my 87 GL converted to a camper by adding a fiberglass
poptop(similiar to Westphalia) with canvas sides and upper berth.  The
conversion was well done and nicely finished.  The vendor can supply
cabinetry and most any type of appliance currently available for the
Westphalia, including propane stove, fridge, and sink.  The vendor does
business in Northern California and conversions can usually be completed
in two days.  Interested parties may reply to dhzim@pacbell.net for more
info