Dear Vanheads,
Allow me to clear up the block heater part number confusion.
The bolt on the bottom of the case block heater is manufactured by Pyroil
of Canada.  It is distributed through North America primarily through
NAPA/Balkamp stores and through other retailers such as BusDepot and
Vanagain.com.  The part number for this item has been superceded from
ZVP 289-104 to 605-1500 by Pyroil, the manufacturer and by NAPA stores.
I purchased this item through NAPA under the new part number; 605-1500 for
approx. $42.00.  So far, this heater has given my van some much-needed help
this season.  I live in SW Missouri and the cold is brief but can be
bitter, not like Canada but still 0 for a couple of weeks is cold enough.
I will be investing in a coolant heater of some type for next year.
I DO HAVE one of these block heaters extra if you have a need.  E-mail for
more info.
Hope this helps anyone whom is too cold for a quiet start.
JB
'89 GL Wolfsburg  (Road Whale)
'82 MB 240D  (Slo Mo)