Cool! Look forward to the results of your experiments!

Have found that a Michelob Big Mouth cap is threaded the same as the spigot cap, but needs to be shortened a bit to get a seal on the neck (of course, I may have to sacrifice myself and it may take several beers to get it right!! )

Given the concern about RTV, plan to build it without RTV... maybe could use the old Permatex gasket sealer - the funky brownish stuff out of the tube... should resist just about anything...??

Cheers!

Jim