TL;DR: Four strangers met on Pinside to execute a long-distance trade.
Shortly after I posted on Pinside about my 1932 Cloverleaf, I was contacted by Pinsider Cait001. She wanted to know if I'd ever consider trading it and, we got into a PM chat about our wishlist Pre-War pin games. It turns out she has two Signals - a Jr. and a Sr. - which are on my list. Cloverleaf is very cool and very rare, but I knew I'd prefer a game with a mechanical playfield feature. We tentatively agreed to a one-for-one trade, but the problem was that I'm in Ohio and she's in Ontario and neither of us wanted to make a long drive or risk shipping our games.
We both understood that Allentown is the Mecca for pinball trades and that collectors and restorers from our respective areas (all over, really) made the trip and haul games back and forth. So we put out the call. Pinsider Ballypin, who lives about 45 minutes from me and whom I met at Pincinnati said he had room in his truck and would be willing to make my trade. Cait001 called on her friend Mike, who was going to make the trip down from Canada. Then it was just a matter of waiting for May to arrive.
At the end of April, I sent out a mass email introducing everyone who would be involved in this caper including contact info. Ballypin called Mike to set a time and place to meet in Pennsylvania. Cait001 and Mike worked out delivery of Signal Sr. and I did the same with Ballypin. I drove over to Ballypin's house a week before his trip and we had a great chat - he's an excellent guy who is really knowledgeable and seems to know every pinhead in the tri-state area.
On the Friday of Allentown, Ballypin texted me that he the trade was done. He attended to some business of his own and headed back that night. The next day, he gave me a call from Columbus and two hours later was at my door. He showed off his finds and related his adventures before helping bring Signal Sr. inside and setting it up. After a little tinkering, I got the mechanics and the bell working and it's beautiful! I hope to hear from Cait001 soon that Cloverleaf made it back to Canada safely.
Thanks to everyone involved - the levels of trust and generosity are really overwhelming! I want to thank all the Pinside moderators and architects for maintaining a great resource that made this possible.