A switch on the relay is better, but you can also wire the chime coil directly to the coil on the score reel relay. It works.

I wired a one point bell for my Royal Guard to the 0-9 unit on that game because the clapper bell associated with the unit never sounded worth a damn. It has had no impact at all on the operation of the unit.

Isn't your solution, wiring a relay to the relay, basically the same thing? Or am I reading what you're proposing incorrectly?

Sure, depending on the resistance of the coil you use. But still, it's not drawing so much current that it impacts on the original coil that was already there. These are two low resistance coils so the current draw is pretty high for both, and they work fine.

Either way will work. Just direct wiring it all up is just a shortcut method.

Williams bells and Gottlieb bells really don't have much difference between them. Now, if you're talking Williams chimes vs. Gottlieb chimes, that's another deal altogether.

Williams did a lot of things really well. Chimes were not one of them. Their chimes sound like two pipes banging together. Horribly clanky. I put a Gottlieb chime box in a Grand Prix. Strangely, they don't sound quite as good in the GP as they do in a Gottlieb, but they sound a hell of a lot better than the Williams chimes do.