time-sert..yea..I was a bit past that. I completely disassembled the head and die-ground out the entire mounting area and then had a friend build/weld it back in, cut it off about right and then tapped and drilled a new hole that feels like it was in close to the right place....now my problem...
I did have the exact same problem with my bike, broke that bolt off last year.
For starters, I can definitively say don't ride with that bolt broken, I could notice pretty obviously the lack of responsiveness when turning right at slow speed the most. As for repair, you seem to have gotten there...
I just got some Leos on today. WITH the db killers I'm quite happy :)
still noticably louder than stock. But it wasn't much after 4th gear and up. it comes with some bolt hole fillers and a note about if you take out the db killers. and warns that it won't be "e-approved" afterwards...which...
just a note that I'll add for you. There happens to be a sizable quarry right between you and the fire..its not a complete fire break but if it comes to that I'm sure it will be very helpful...not that I wouldn't have all the valuable gadgets and important documents neatly packed up just in...