I used a longer bolt and nut for my driverside front. Works just fine. Those corner bolts get attacked by o2 over the years unlike the interior ones that are protected by the block. That's why they rust so fast and snap.

 

This seems to be a real problem. I still need to do mine, but just haven't had the time. I want to do it at work so in case I do have this same problem I will have everything there I need to get a broken bolt out.

 

I ended up just putting a longer grade 5 bolt and hex nut on the back side. I drilled the jb weld with a 1/4" drill for the 5/16-18 tap and wasn't impressed with the apperance of the jb weld. It was real powdery, almost looked like some sort of clay. So far she's running good. No more knocking during acceleration, and seems to idle a little bit smoother. The plenum kit I used was one from e-bay for 55 bucks. So far no negative issues with it.

 

Doing mine this week ill soak em with pb blaster 1st