Muffler shop had to cut it out, it was like both the bung and sensor were oval. Idle was loping on the way over, and a perfectly solid 900 rpm after the new 02 sensor.  Put a new bung in the cat so it looks good to anyone who cares.  $55 for the sensor and $75 for the installation.  I'm vindicated!

All I have to do is convince my son it's fixed, and that will just take some driving time.

On another subject, my '85's conversion will be a rebuilt '92 Subaru 2.2.  OBD1 with knock sensor and much simpler than the later model 2.5s. I'll take simplicity over power at this point. 

Stuart