Hi @walkerbk - more data for you, and pictures. The stub in the tranny tunnel that the pivot fits into, and how the ebrake shaft fits into it. The white delrin bushing fits inside the stub, and the black cover fits around the outside of the stub to keep stuff out of the greased delrin bushing. I measured the outside diameter of the stub, and it measures 28.5mm which matches my earlier measurement of the "big hole side" of the cover. There is probably some additional thickness with the bedliner coating in my tranny tunnel, but as long as the cover has some stretch to it, it should be able to fit over the stub to provide the seal. As far as how the cover will hold up under the vehicle - I suppose it would have exposure to grease/oil/water, maybe some heat from the exhaust?
Let me know how you want to proceed - I'd still be willing to ship you my black cover for comparison if that would help. Thanks!