4.0 Timming chain nightmare

[DEDII]

Hello everyone I like a lot of people have a question about the timming chain replacement on a 2001 ford sports trac. I'm trying to get the rear chain sprocket on with the $75 reverse thread bolt Torqued to 64 ft-lb? The threads are cleaned out and so far I have snapped 2 of them even went a bought a new torque wrench that goes in reverse. It doesn't feel like they are even at 30 ft-lb when they bust . I'm 150 pounds and I was using my left hand so I wasn't over tightening lol... $75 a pop I would only like to do it one more time. I mean I've got mouths to pay and habits to feed lol