This is helpful and thanks for the ideas.

I'm also considering the following:

1. Extra house battery that is charged by main battery when running
2. 12 volt converter for the block heater plug
3. Timer - to come on 3 hours before intended startup

Seems like it'd work.

Don

__________________
DAILY DRIVERS:
'84 300DT 298k (Aubrey's)
'99.5 Jetta TDI IV 251k (Julie's)
'97 Jetta TDI 127k (Amber's)
'97 Jetta TDI 186k (Matt's)
'96 Passat TDI 237k (Don's
'84 300D 211k Mint (Arne- Undergoing Greasecar Conversion)

SOLD:
'82 240D 229k (Matt's - Converted-300DT w/ 4 speed