tails, full suits, what to wear underneath

Sorry, I know my questions haven't been construction related lately. >< Anyway, I'm getting my partial upgraded to a full suit and I have an inquiry. I was originally going to wear like some spandex workout pants (and maybe buy an underarmor top) underneath, but I also had her make me a new tail. The tail is worn with a belt and belt loops. Problem is, I'm not sure how that's going to work in a full suit!

What do you guys do? Is there a certain kind of pants that would work (and not cook me alive) inside a full suit? I was thinking of maybe making some makeshift belt loops for the pants I intend to wear....but I'd like to avoid altering these pants in such a fashion because they -are- nice workout pants. ;) Any tips, advice from full suit wearers?

Thanks guys!