Donald, sorry to hear of your problems.

I lived in Alaska for many years and all cars brought up from warmer
climes always had climate adjustment problems to work through the first
winter they were there.

The cold will overstress every weak point and cause a failure or shutdown.

Since the van is in a warm place and any frozen water is thawing,
Immediately put some "HEET" or some other de-icing fluid  in with your
fuel to start removing any water. Also lube all your door locks with a
true cold weather lubricant -- graphite or something dry. You want to
keep moisture out of them.

As for the oil seal problems, you have already found what happens to old
seal in real cold weather. Replace with new as you are doing. Hoses are
the same way. You don't want to be caught way out somewhere in the cold
and be stranded. Be sure your coolant antifreeze is adequate for the
temperature ranges.

Disconnect the power steering lines at the power steering rack and at
the pump and blow some air through to remove any water. Then reconnect
and refill. It will take a few minutes of running to circulate the fluid
through the system, and then you will need to add more fluid. With the
wheels off the ground, cycle the steering right and left to the stops
several times with the engine running. The pumping action and pressure
will purge all air from the lines, then you will need to top off the
tank. Use only Dextron II or III ATF. DO NOT use any fluids that say
"Power Steering Fluid" on the container.

  I can't be of any help on the reast of your troubles. Just be aware
that you will probably continue to have cold related problems until you
get them caught up. Then your van should perform nicely. I had an 85 GL
that I had to put through its paces until I got all cold weather issues
resolved. Then it performed nicely for the next several years in that
Alaska Cold.

John Rodgers
88 GL Driver