I have had several go-rounds with the Magnum thermostat housing.

Notice that the official Magnum thermostat gasket has been revised at least 3 times.

The 1995 FSM advises loosening the air conditioner compressor bracket and swinging the compressor over without undoing any freon connections to service the thermostat.

I resisted this the first 2 times.
On the third time I followed the FSM to the letter and found it actually did not take any more total time and gave you far more space to get everything right without the “down in the hole” maneuvering and long wrench extensions.

The last time I skipped the gasket and used the cheese whiz “Right Stuff.”