Hi Bruce.
Sorry for the lack of colour in this quick sketch. the scanner is sulking tonight for some reason.
Back in the 1950's in these parts of the country, a very popular weather seal for exterior door was a slightly corrugated strip of spring brass, fitted to the door frame with brass nails. a quarter inch flat strip of the brass went at the outer edge of the frame and the brass strip angled in towards the door.
I think a similar concept in spring steel might have been used on the HUW to activate the door blackout switch. Very rough drawing attached.
A spring steel strip of the required width would mount to the two exterior holes close to the door frame. the strip would wrap around the door frame at 90 degrees and fit flush to the inner frame surface maybe one quarter to three eighths of an inch. This would prevent the door from binding against the metal strip. as the door moves further inward, it starts to flatten the spring steel against the door frame. at the open end of the strip, a small metal cup is rivited. this cup fits over the switch plunger and inside the plunger hole in the frame. The cup would need to be long enough to stay inside the door frame with the door open to avoid snagging on the frame.
I think the travel distance of the plunger will be critical for the right switch, and also as you mentioned, you need to find a spring loaded safety switch that shuts off when released, not turns on.
In the photo you posted of the two original switches, the one on the left looks like it has a circular collar fitted part way down the plunger. That might be a means for the cup on the spring metal strip to better engage with the plunger. Or I am dreaming again.
Hope this helps and doesn't muddy the waters too much.
David
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