Easy, not really.  You must first remove the engine pulley, this is a high torque nut.  I had to make a tool like that shown in the Bently manual.  To get access to the pulley, you will need to remove the muffler and splash guard sheetmetal.  Once the pulley is off, removing the pump is easy.  When installing a pump, you should replace the sealing nuts with new ones.  I would doubt if the old ones would seal a second time.
  ----- Original Message ----- 
  From: John Lunetta 1990 Vanagon GL 
  To: vanagon@GERRY.VANAGON.COM 
  Sent: Thursday, August 16, 2001 8:01 AM
  Subject: oil pump

  Does anyone know how to replace the oil pump on a 1990 GL 2.1, the easy way 
  if there is, and the tools I will need. Thanks  John 1990 GL 

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