Dave,
I just used a can of Krylon artists acrylic clear. It is a lacquer based product, and dries in about 20 seconds. I just did the triggerguard, inside and out, after a wipe with wax and grease remover, and I was done. Maybe 2 minutes of time invested.
When I did my 12 gauge, I mixed up and sprayed Brownell's baking lacquer, out of my Binks No. 7 gun. Bigger job, bigger deal, bigger mess.
I used a different product on my Lefever Nitro Special, I threw the can away when I was done, it didn't lay down as nice, but, I suppose it will still protect the case colors, which, was all I was after.
Best,
Ted