i just went through this less than 5 days ago...i took the route not recommended by replacing mine with a stock replacement...it was only 50 bucks for the balancer compared to the 350 for the bhj balancer......
things to look in for.....
first ur gonna have to drill out both left in neck of hardmonic balancer.....its alluminuin so its very easy to drill in to....the use self-taping screws and pull out with plyers....(look at pic)
second will be the broken bolt.....first check to see if it is loose(most are when broken) if not use an easy-out to get out.....allso pretty easy to remove.....
third check crank sensor.....may have been damage during braking of balancer......mine wasnt but u never know....
when ur ready so install replacement....be sure to have a new bolt(one from a newer style mustang 3.8 works) a balancer installer (autozone rental) a lil loctite.....some gasket sealer and patience.....
when u go to tighten the crank bolt be sure to prevent the motor from turning......some recommend jammin the flywheel or pressure plate or even putting the car into drive..........i personally tighten the bolt as hard as i could.......the reinstalled all belts and had a friend hold belts and then i tighten it.....the tensioners and pulleys applied plenty of resistance for me to tighten the bolt to 120lbs....
if u go with the bhj balancer follow theses instructions:
http://www.mn12performance.com/mn12how-to/BHJ/BHJ-install.html
n e othe q's...let me know or any one else on here
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