I'm wondering if this guy is even a semi reg, his stats actually look kind of more like an aggro-ish fish at 10NL, and his flop sizing compounds that he's likely bad. I definitely do like taking contol of this hand on the turn because he's calling this lightly most of the time and may checkback some Tx hands etc that have sd value, or even spades.

Here's a likely range he'll continue with on the turn

Board: Qc Ts 8d 6s
Dead:

equity win tie pots won pots tied
Hand 0: 56.568% { KdQd }
Hand 1: 43.432% { 66+, AsKs, AQs, AsJs, ATs, As9s, As8s, Ad7d, As7s, As5s, As4s, As3s, As2s, KTs+, Q9s+, J9s+, T8s+, 97s+, 87s, AQo+, ATo, KQo, KTo, QTo+, JTo }

I think it's easily this wide and would infact weight it more towards marginal hands due to his flop sizing, giving you more equity than this.

River is a snap fold, and I'm not even puking.