Never assume that if the suffix letter is the only difference, that it must be okay to choose as a replacement part.  Any time a VW PN has a different suffix letter, that indicates that it's a variation of the part, and is designed for a specific application.  Generally, lower suffix letters are usually for earlier versions and higher letters are for later changes or other versions.  On occasion, it's a totally redesigned part and would never fit anything except what it's designed for.

Mike B.
  ----- Original Message ----- 
  From: AD Felder 
  To: vanagon@GERRY.VANAGON.COM 
  Sent: Saturday, April 11, 2009 11:19 PM
  Subject: radiators

  Anyone know if there is any difference (other than the letter appendage) between radiator 068 121 253A for a diesel 82 and radiator 068 121 253E for watercooled 84-91? Can the more available E version be used to replace an A version in an 82 diesel? fasten points the same?

  Appears I have a crack, lower right, rear face in the plastic near the return hose outlet.