hello, i got some heads and damn it, somebody overtightened a bolt and broke the very tip off of the bolt in the head and pulled the threads out and looks like they tried to retap it because the threads were very brittle. i tried to put my rockers on and i was not forcing them on. it would not stop spinning i looked and there was ****nit all in the hole. i know there is something stuck on the bottom of the hole because i put something down in there and it would not go to the bottom like it did in the other holes. will a helicoil or 2 fix this or do you think that they will eventually or often pull out while driving. i have an f cam and .600 lift dual valve springs installed. i am in a panic. what size do i need also. and do the helicoil come in a one thread style fits all or is there a certain type for the rocker bolts i have.