Hi ludikris , I'm a fairly new and proud HH owner, it is actually THE machine written about on another posting where the previous owner intended to convert it to multiball but never got around to it (but did an amazing job of redoing the playfields, beautiful game!). Anyway, when I bought it I thought I would probably finish out the multiball project at some point down the road, so I literally have a bag of parts that should be everything needed for the conversion. But I had enough trouble getting the machine back to a reliable state in my own home (after doing a cabinet revamp) that I have decided I'm just not up for undertaking the level of effort required, plus I just am loving the game as-is ... now it is 100% working, honestly I'm scared to do anything drastic and I'm happy with it
Looking at the parts list link, I definitely have the main hardware needed (being the 3-ball release mechanism, and the two ball-gate mechanisms). Also have the additional relay parts, but you might not even need those if you just modify the existing relay (per other writeups on Pinside).
The things I don't have are probably the easier things to find: trough switch, posts, and the wire gate that prevents balls from going into the cellar back down the VUK tube (that is already installed on my game, and I decided I am keeping that to save a little wear and tear on the VUK from kicking balls back up).
So rather than a bag of parts gathering dust on my shelf, if you are interested in getting the whole parts lot let me know and I'll give you a heck of deal, would be happy to see the results of your efforts (and maybe when I'm fully retired in a decade who knows, I might go for the multiball mod myself!).
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