Thanks GuyG,
I wouldn't use a Buddy style heater inside the van since they produce carbon monoxide and vent directly into the living space. I know they have an oxygen sensor but I wouldn't want to bet my life (literally) that it could never fail.
I wasn't installing a propane system in the van so that excluded a propane furnace. Electric heat is out since you can't run them off batteries and my camping is almost always boondocking so there won't be any outlets available.
By process of elimination that left the Espar/Webasto style heater. They are both about the same. I choose the Webasto over the Espar simply because I got a good deal on this one on ebay.
Webasto heater install continued:
Reuse the gasket that fits between the Combustion Air Fan and the Heat Exchanger.

Screw the two together.

Put it back on the work mount.

Run the two sets of wires under the side clip.

Take the Lower Housing Shell and clean it.


Clean the Heater Air Intake.

There's a small lip in the Lower Housing Shell that the Heater Air Intake fits into.

As the heater is lowered into the Lower Housing Shell the Heater Air Intake has to be fit both onto the front of the Combustion Air Fan and behind the small lip in the shell.


There is a small round catch like this on each side of the heater.

It needs to pop into the corresponding hole on the Lower Housing Shell.

Next up is the Control Unit.
Look down between the heater and Lower Housing Shell. You can see the Arrestor Groove.

The bottom edge of the Control Unit fits into that groove.

Be sure it's properly seated before screwing into place.

Next are the X1 through X5 connectors.

Remember that the color of the sticker matches the color of the wire.

continued: