When I fitted brake lights to my barn fresh Henrietta, I went away from the usual, new motorcycle pull switch used on all my restored cars. This is what I used
This switch came from an 80s Subaru. The metal stem is threaded so the engagement of the plunger .can be adjusted at the switch. The rusty metal bracket is the same material that I used to make her trayside hinges.
More modern cars have clip-in-place plastic switches which would need a slotted hole in the bracket for adjustments
I have two extra spare metal switches and a fixed plastic one, all for the princely sum of $5 at the wrecking yard.
Allan from down undet