The t-stat wire may be rated at 300v, but the system energized is rated at 24v, hence the 2 diff species. Inductance may not be an issue(digital, microprocessor controlled t-stats very popular nowadays), but accidental cross contact could burn up a few things. How about the bare grounding conductor in that disco, starts out at the rear, ends up at front lower left side-I'd feel better if that was more isolated from the live front of the disco...And yes, wtf's with that 1" splice??
