Thank you everyone, exactly the responses I was expecting, pretty much split.
Here was my thinking....He's not shown any aggression whatsoever until the river when he put me pretty much all-in (was about $8 short of that) and as such, by the end of the turn play, I put him on a draw.
I didn't value bet the river as I'd have to fold to a raise, and he'd have to fold a raggy A, missed draw (I was only worried about A8 and backdoor diamonds) so I checked hoping he would check it down, but be prepared to make a call if he bet.
The call was very uncomfortable for me to make, but went with my read.
I called and he showed
for the busted gutshot and I took down $180