Before investing in a new tank take Jim D.s advise and see a REAL propane
dealer (ie: Hank from King of the Hill).  We were sure we needed a new tank
in our '85 Westy and after being sent all over eastern MA and RI, found out
all we needed to do was see a qualified propane dealer.  He repaired our
tank by installing a new fill valve and "spitter valve" which took the
place of the original overflow valve VW had.  We did have to sand and
repaint the tank, remove and then reinstall the metal plate to check
underneath for rust through but that took a whole two hours out of our day.
 The total repair cost about $45.00.  The tank was stamped with the
recirtification date, refilled and we were on our way.  Unless your tank is
eaten through, you probably won't need a new one.

Happy Tails,

Wendy & John
'85 Westy,   "S-CAPE"