cannot get oil filter out have taken 11 of the 12 bolts out of sump . one bolt as been rounded off. any suggestions ? can i drill it out without causing damage. plz help

You can usually drill the head of those bolts, use a 1/4 in drill.

Go down to your local auto parts shop and buy something called an EZ-Out, or some such brand, they'll know what you mean if they're worth their salt. Screw it in to the small hole you've drilled and carefully tighten it until it 'bites' in. What's left of the screw will be spun in reverse and hopefully come out, easily. Failing that, centre it as best you can with a punch and drill it out in ever-increasing sizes hopefully without damaging the threads as you go. You can pick out the bits of screw. Afterwards tap it out with a 6x1.0 thread tap. Alternately, can you grab the remaining piece with some well-placed Visegrips?

thankgod just managed to get it out. now to remove the filter. thanks