360 LA getting oil in #3 cylinder.

Looking over everything before starting reassembly. Kinda wish the head bolts were a little longer. I screwed the head bolts into the block just to see how far they would go and all but the rear long bolts on each side would bury the threads even with the deck. The rear long bolts had about ½ round of threads still showing.
Then I put the old ARP bolts with washers through one head and this is what I get.

20230403_073745.jpgOnly about ½ the threads are going into the block. And since the threads are countersunk into the block, and with headgaskets, I'm getting less than this.
Seems like I read somewhere that a bolt should thread in at least 1½ times bolt diameter. That would be 0.75" for 0.5" bolt and there is only 0.67 sticking out of the head.
Would ARP studs do better? Thanks in advance.