well... start by putting him on a hand range.
for example (note this is not the hand range i would actually consider here, but just for simplicity):

he has a worse 9: 40% of the time
he has a J: 20% of the time
he has overcards without an ace: 20% of the time
he has overcards with an ace: 20% of the time

ok if this is his range, what is your best play?
it doesnt matter if in this case he does or does not have the J, you cant possibly know that for sure. all that matters is giving him LIKELY hands, and playing according to that. here i would say you are well ahead of, possibly even reverse dominating, a lot of his hand range. as such you need to get bets in on the flop.