Bores look good does yours have the 1 piece light seal o ring rear main i found most of my leaks come from further up & weep down the sides making it look like a rear main leak also along the back of the valley cover check the rear oil gallery bungs as well i use the loctite white thread seal on everything & gascachink on the pan
I can see it coming from the pan seal, rear main was dry, going to reseal all the galleys back there and if I can get the cam plug out and silicone that in instead of the gaskasinch stuff just to be sure. Going to go over everything.