Just some tips and observations based on being about half-way through
completely replacing the cooling system on my '87 Westfalia with manual
trans and A/C. This job has to be one of the more tedious and
time-consuming ways in which one can interact with one's vanagon. I can
see why the inline-4 engine conversion is so popular. Just simplifying
the cooling system is almost worth doing the conversion. The wbx with
air conditioning is particularly challenging.

1) The use of hose clamp pliers, as opposed to struggling with regular
pliers, makes a huge difference on some of the more difficult spring
clamps. I used pliers with a toothed device for holding the jaws in
specific position, again nice to have with the larger spring clamps. Got
mine at the local Kragen's, about $14.

2) I found that it was easier to replace the oil cooler hoses, as well
as the water pipe that comes from the thermostat, BEFORE installing the
water pump. It's necessary to get the hoses positioned on the cooler
just right, and them clamped, and the water pump is in the way when
doing this.

3) I replaced the oil cooler O-ring. However, before fully tightening
the nut that secures it, I left it loose enough so that the cooler could
rotate. It was easier to maneuver the two small elbow hoses into
position on the cooler this way. There isn't much room to work.

4) The thermostat housing is easier to install into position by first
installing the lower half, installing all clamps, installing the
thermostat, and then installing the upper half. I tried to install the
whole thing already assembled, but it's too bulky to maneuver into
position. I also changed out the two temp senders while it was out.

5) The hose that goes from the right-hand cylinder head to the plastic
TEE junction (S-shaped hose) runs very close to the #1 cylinder exhaust
pipe. My old hose had split at this location, which was what prompted me
to undertake this project in the first place. I suspect that excess heat
broke the hose down at this point. The new replacement hose is EPDM,
which I believe is more heat resistant than plain rubber. I'm thinking
of also wrapping this particular hose in aluminum foil to reflect the
heat of the exhaust pipe away from it.

More insights as I gain them :)

dan