I took the Westy back to the mechanic who installed the AVP motor and they
took off the flywheel and removed the front engine seal with me watching.  It
had a big glob of engine sealant stuck to it.  There was also a cut in the
rear part of the seal (the part that faces the engine).  Their best theory
was that the permetex engine sealant goo was what made the problem.

I will send the seal off to AVP tomorrow and should hear from them later this
week.  Thanks for all the help from the list.
Peter & Zippy