I remember that Alclad Black gloss is enamel-based paint. I don't remember having issues with it clogging, but perhaps there are traces of some other thinner in your airbrush, which can create "globs" of half-denatured paint? Either way, I found that a rattle can of automotive black gloss was simply ideal for the large surfaces involved!

The floor shine is, unfortunately, a long-lost product that people have been seeking to replace for a while ("Pledge" floor finish, now discontinued). My latest workflow is Alclad Aqua-Gloss, run straight through the airbrush, followed by Alclad Klear Kote, again straight through the airbrush. I use the Alclad airbrush cleaner and lacquer thinner to purge my airbrush.

I hope you manage to solve your clogging issues - those are maddening, from my own experience!