1800E dash switch thread size
 

My 1800E was missing the panel light rheostat when I bought it, and I secured one from Flea-bay. Unfortunately it didn't come with a nut or washer to secure it in the dash, I assumed the nut would be some standard thread, but no luck finding one. I'm guessing it might be metric but can't seem to find a nut , SAE or metric.

Anyone know the proper size?

TIA.

I don't know, but in situations like this I run a thread gauge across the part. They're really handy, and cheap.