Thanks for all of the advice. Now I get it — the compression fitting threads into a pipe-thread hole. I hadn’t crawled under the truck to take a look yet. Waiting until Saturday for that.
I bought the 1/8” NPT plug while I was at the hardware store just-in-case (only a couple of bucks) so I should be ready to go.
One more question . . . is Teflon tape good enough to put on the threads or do I have to use pipe dope?
I just want to get the truck put away for now so I’ll do the full repair next spring (line, fittings, gauge, etc).
