CMC Speedster Dash Question

If you decide to use the later style VW switches you'll have to go very thin with the FG. Use a 3" wheel on a drill and work it slowly on the back side to reduce the FG thickness. BTW I run a shop vac nearby it pulls a lot of the dust away.  Me, I have used aftermarket switches that have longer threaded shaft along with relays. Then I switched over to these earlier year VW switches that have a slightly longer threaded shaft . They are HD and can handle normal circuits without having to use a replay.    VW Bug Bus Ghia T3 Headlight Switch 311941531A Made In Brazil | eBay

Long sleeve shirt and googles, CUZ:

Measles' make you mumpy and mumps' will make you lumpy
And Chicken pox will make you jump and twitch
The common cold will fool you
And whooping cough will cool you
But sanding fiberglass Lord will make you itch

Your gonna need an ocean
Of calamine lotion
You'll be scratchin' like a hound
The minute you start to mess around

I had the same problem, so I counter-sunk from the back of the dash an area wide enough for the switch or whatever to clear, and deep enough (from the rear) to leave 1/8" - 3/16" thickness for the switch.  It's been a while, but I believe that I used a rasp bit in a Dremel with the Dremel attachment used for setting depth for removing grout from ceramic tile.  Get your depth set, draw a circle around the hole with a Sharpie as a guide and have at it.

I did it the same way as Gordon with a rounded rasp/Dremel, but freehand. And a shop vac directly under the back of the dash.

Only grind just enough to get the nuts on the front.

@WOLFGANG posted:

Long sleeve shirt and googles, CUZ:

Measles' make you mumpy and mumps' will make you lumpy
And Chicken pox will make you jump and twitch
The common cold will fool you
And whooping cough will cool you
But sanding fiberglass Lord will make you itch

Your gonna need an ocean
Of calamine lotion
You'll be scratchin' like a hound
The minute you start to mess around

And a good respirator. The powdered resin from grinding/sanding fiberglass  is really toxic.