Uh Bruce, no offence but I think you've been taken by an urban myth.
The angle of the plugs entry into the combustion chamber is controlled
by the angle of the spark plug hole or port. Any lop-sided shim/washer
would only effect the seal at the base of the plug. I can't imagine a
washer that could overpower and reorient a plug bore.  If you want to
change the angle you'd have to drill and tap the holes where you want
them.   yes? No?
On Friday, June 11, 2004, at 03:28  PM, Automatic digest processor
wrote:

> Any of you hot rodders out there remember the indexing washers for
> sparkplugs? These were essentially shims that you would use to "aim"
> your
> spark plug when installing your plugs in the head. When torqued, if
> your
> plug wasn't at the optimum angle (spark not facing the most turbulent
> fuel/air mixture), you pulled the plug out threw in one or two more
> indexing
> washers and the angle of the plug could be aimed to optimize burn for
> most
> power (they weren't worried about emissions in those days, but a
> better burn
> is cleaner in this case).