My Dad and I also knackered a really nice 2-foot breaker bar, invented some new swear-words and lost a few pounds of sweat trying to undo the angle drive nut on VIN #4400 a while back. In the end it had to be sorted at a local garage which has experience in dealing with DeLoreans.
The general consensus seems to be that it's a pain of a job, but very satisfying once completed. I was lucky enough to find a PJ Grady "hardcore" angle drive with strong stainless components for a bargain on eBay about a year ago. A year on, this piece of kit has been faultless...might be the way to go to avoid having to pull the angle drive nut off again in the future?
Phil Peters *too much beer to type* VIN #4400 (Currently at DeLorean Motors UK)