Still have the old pump?
If you do...tear it apart and get out the machinist straight edge and check both halves for flatness.

Glad you got it fixed!

 

Thanks. I actually have it in bits on my bench. Sat here for half an hour going over it trying to work out what the mistake I made was.

Both halfs are dead straight, pass vacuum test, and whatever the problem is it was created by me (not the cause for the original tear down.

I'd love to know for sure just for my own piece of mind. front stator is the only thing that I cannot conclusively confirm is sealing.