PeachParts Mercedes-Benz Forum - '83 240D W123 - Removal of oil filter housing

I need to pull off the oil filter housing to change the oil thermostat. As far as I can tell from the service manual's description, my thermostat is stuck closed. I don't have the special thermometer that's described in the service manual, but after driving, the oil filter housing is hot to the touch while the oil cooler next to the radiator is barely warm.

With that said, do I have to drain all the oil to remove the filter housing?

On one hand, I just changed the oil barely 600 miles ago, so it seems like a waste to drain it all out and put fresh stuff in. Also, while the engine's sitting, most of the oil should drain back down into the sump pan anyway.

On the other hand, removing the filter housing is probably going to be pretty messy to begin with, and I'll be sad if I disconnect the lines that go to the oil cooler and two quarts gush out onto me. Black gold. Texas tea. Oil, that is.

Any hints? Thanks.

- Nathan
'83 240D, 250k miles

P.S. I thought I already posted this, but I don't see it on the board...