On Wed, 25 Oct 2017 21:15:52 -0400, micky
wrote:

I need to put a momentary on switch in my dashboard, and the one I
bought doesn't have a hex nut for the top nut but a round serrated ring
to hold the switch in place.

I use these:
https://www.harborfreight.com/3-piece-long-reach-hose-grip-pliers-37909.html
$15 for 3 pliers. They're made for removing automotive hoses, vacuum
lines, fuel lines, etc. You can't tell from the photo, but the
insides of the cricular area is serrated for a better grip, which
should mate somewhat with your switch nut. The 45 degree tip angle is
also handy for clearing other junk on a front panel.

Mo
https://www.google.com/search?q=hose+grip+pliers&tbm=isch

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558