Jeff,

        I wouldn't be too concerned about the weight... there was a "fifth seat"
option offered by VW for the '85 Westies (with the 1.9 engine). This was a
forward-facing seat that mounted to the usual middle seat rails, but left
enough clearance to open the cabinets. I;'ve heard that thisseat was
discontinued after crash-testing the '85...

        Your '89, with it's (massively more powerful :-) 2.1 should handle the
extra weight just fine.

Tim