I'm brewing tomorrow and can confirm that for you. Like day_tripper, I've hung onto my ancient Italian carboys for some dumb reason--maybe I'll make wine some day even though I don't much care for wine. Can't bare to get rid of them, I guess. I made a lot of beer in them and learned a lot.
Anyway, I'm all but certain that the standard TILT will fit into a 6gal carboy neck. That doesn't concern me in the least. Getting it out, though... That's gotta be like dropping a pick into an acoustic guitar's sound hole. Shakey, shakey, shakey, shakey, cuss, cuss, cuss, shakey, shakey, shakey, cuss, cuss, cuss, etc.