Water pump bolts

[Isensee@aol.com]

I started to replace the water pump on my Bricklin today. The bolts are rusty
and I rounded the heads on three of them. Anyone have a good suggestion for
getting them out? I have tried drilling and using bolt extractors in the past,
but have never had good luck with them. I think I once saw some special
sockets which bite into the head of the bolt, but I can't remember where I saw
them. Anyone know of a source?

Scott Isensee