BUR223673449
Then it has the mod to address the ETN37 overshoot issue.

Do you mean -R like a command line?
No, I meant the PK4 assy number... usually on the label right above "BURxxx". On one of mine it's "10-10094-R2"

There's probably no real reason to put a zener on VDD. The overshoot was only on the VPP/MCLR high-voltage generator.