Very easy to remove, just a few bolts and screws to get the overhead unit off
and undo the the A/C lines (reclaim freon first) and unplug some wires and
the overhead unit can go out the door.  Undoing the A/C lines from the
condensor and compressor and then pulling them is the hardest part of
removing the entire system (along with pulling the condensor itself as I
believe you have to remove the radiator to do this).  Taking the compressor
off of the motor with the associated brackets is easy.
I would remove every thing along with the wiring harness and offer it for
sale on the List (some folks want these).  Only holes to plug will be the
ones for the A/C lines that go through the floor behind the driver's seat.

These A/C units work pretty well with R-12, rather poorly with R134A unless
you do a complete system flush and replace the expansion valve (this brings
it up to the level of near R-12).

The real problem with these units is the weakness of the airflow caused by
poor fan output in the overhead unit.  The cold air is there but the fans
just don't seem to be able to push it out fast enough to get the van nice and
cool.
Anyone figured out a way to get more volume of air going through this unit?
I was thinking of using fans from the later model vans (they push air all the
way from the back of the van and the air really moves nicely), or maybe
setting up a relay and larger electrical supply wire from the battery to see
if we are just having a voltage drop problem.
I have sealed all of the air leaks in the overhead unit but it really just
doesn't help that much.
Any ideas welcome.

Thanks,
Ken Wilford (Certified Air Conditioning Tech)
http://www.vanagain.com
John 3:16
Phone: (856)-765-1583
Shop:   (856)-327-0027
Fax:     (856)-327-2242