HI J:
Here some shots of the "auto" one installed.
There are no obvious "unlock" method(s) that I can see(preferred the old one).
I will wait and see if ideas come in as I installed it "locked".
If the worst comes down I will take it out, "unlock" the plunger and wire it shut as you had mentioned then release when bolted back in.
A annoying little task but necessary.
Thanks for any hints!