On my '81 Westy, as near as I can tell, the wiper arms are identical.  I didn't take them off to hold them side by side, but I did use a tape, and I can't measure any difference.  Neither has a part number that I could find, and I don't know if they are original.
  ----- Original Message ----- 
  From: Keith & Lynn C. 
  To: vanagon@GERRY.VANAGON.COM 
  Sent: Sunday, May 14, 2000 6:16 PM
  Subject: wiper arms

  ok ok, a small question. I have 2 wiper arms in my hands, just painted,
  2 different p/n and slight differences in length and bend. p/n's are 192
  138 and 191.385. Van is an 81 Westy. Now then, which is the driver side
  and which is the passenger?? Are they correct for the model I have?
  Cheers,
  Keith

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