Thank you very much Ranger, I appreciate your time on the matter. Nice pic, I do know that we are talking about the same component now, which is getting closer!
My nutter googling let me to several references to the BBD, but only one to the YF. The one regarding the YF spoke of removing the solenoid/stepper motor and blocking the area off with a plate, and also plugging an "angled bleed" metering passage. I cannot find reference to applying voltage to the stepper motor to trick it.
I'm going to find a standard YF or YFA for this vehicle (not mine) before I go that far, but in the meantime if I can get a compromise from the default rich condition, or perform a one time direct voltage application to get the stepper motor to move things to where It becomes the best compromise then we might call it good enough until the proper YF's come home.
I'm sure it will tease out either way, time being solution