I just fixed the wipers on my Gen1 SWB. I thought it was a burned up motor, but that was just the symptom of the real problem, The wiper mount/pivots had gotten either jammed full of crud, overspray from a repaint and rust to were they wouldn't move. I removed the motor, both from the firewall and the motion rod, had to use liberal amounts of a penetrating lube, a 12mm socket and both hands to slowly work it back to life. I repeated the spraying of (WD-40 in my case) and working the arms back and forth until I was happy with the freedom of motion. So, before you burn up your wiper motor, you may want to dig in a little, unbolt it from the firewall and make sure the arms move freely.
-Jon