I'd be surprised if I found a shop that knew what it was (or wasn't):D
If you do a Google search you can find lots of images showing what used to be there.
I would get under that thing, or look down there with a flashlight and see if it's got the lever and what is or isn't there and take it from there.
On the trans, there should be a lever like this fingers pointing at.
Some had a knobbed stud like this and some have a hole the end of a rod goes into.
In any case, this is the throttle pressure control.
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