Originally Posted by Sniper
So a regular 12 pt 13/16th deepwell won't fit?

The thread title didn't answer that question? whistling No, it won't fit. Hence the request for a thin-wall...

I'm surprised this thread is still going! Good to know the high-dollar sockets will do the job.
No, I don't have a lathe. Another one of those "someday" purchases.

My aluminum heads that are going on this winter take a 5/8" hex plug. I should be able to get a standard 5/8" plug socket in through the fender hole and clear the tube (just) so I won't need 13/16" plugs any more up