Live 25/50 hand

[HockeyChecker]

Pretty standard game few regulars, couple nits, and 2 loose business guys which is why I'm sitting. I'm probably seen as fairly LAG but have not done anything out of line so far. Villian has been playing very tag. He has 8.5k, i cover.
Folded to me in SB I complete with 4c5c. Flop is 6c6d7c. I lead out for 100, villain thinks for a bit and makes it 350 more. At this point I'm about 90% sure villain has a 6 based on history and flat call. Turn 8s. I check, villian bets 750, I make it 2900, Villain thinks for a while then shoves. Hero???