Stubborn Clutch to flywheel bolt

[Anonymous]

How do I get it out. Its one with a very short head so that I cannot get a good hold on it and have slipped of it a number of times. It also has crossgrooves in the top of it that I tried using and impact driver on I broke the screwdriver bit. Can I drill it out?
Only other option is to continue driving it and wait until the clutch has completely worn out and then cut the clutch away from the bolt then use big vise grips.
A friend advised me to take the clutch and flywheel off to ensure that I did not have a rear main oil leak but I think I have already rule that out and I cant find any oil around or on the flywheel clutch etc.

 

[addo]

Sounds like more fun than pulling a balancer.

OK, you'll need a 6 point impact socket. Grind the lip down so the slight lead-in bevel on the inside is gone. With one person holding the socket hard against the clutch cover (sandwich it with a hand either side of the assembly), the other applies sharp blows on the breaker bar with a lump hammer. Heat and/or brake fluid in the rear of the threaded hole might help release any bond, too.

Adam.