Maybe Zero selected Kong and Spenser (Senior) because their ancestors's curriculum vitae (I bet in the aftermath Sheriff Kong became a werewolf hunter or something along those lines).
Of course, the Sheriff's near-transformation into a werewolf was ghost-induced, and, since he met his great-grandson during that adventure, it might have given him that revelation: ghosts exist and some of them are bad--the bad ones need to be fought.
We still have to be very careful about family trees, though, and not jump to the conclusion that the names "Spenser" and "Kong" were constant throughout. Anyway, the drawing I posted was a concept sketch of what the Dematerializer might look like if The Ghost Busters took place in the 19th Century--the reason why I ascribed the invention to "Messrs Spenser and Kong"--and the geneaology speculations only came after that.
I agree about the Far West episode, that could have been a pivotal, key moment in the Kong clan history... to the point each Kong developed an increasing ghostbusting "attitude", generation by generation.
I like this whole "steampunk" Ghostbusters project, bring it on!
"Yes, sir. We're the real deal. And no, sir. I don't listen Ray Parker" - Eddie Spenser Jr.