I did not lay it out but the rows of 3 components pictured opposite the fuse seem to be tied to the individual reels and buttons and operate from one of the ICs I cannot find a path from what I believe controls the reels to the relays, I am now of the opinion that the relays control the Jackpot modes. Do we have 2 types of old stop boards and we never realized it? I also noted that what I think is the Jackpot/Payout control on your example is 6 pin while mine is 8. If you have PERTINENT information to add to this post please do, otherwise please don't. I thought it would be better understood in one area.
This information is from other post's from Ken Layton, and teqkng.
