According to the notes on ipdb, Ice Fever was the last sys80A game. It is also of note that the board sticker says "Premier-692 SN5399". Game 692 is El Dorado City of Gold, so this isn't the original MPU (IceFever is 695).

It's interesting though because model 694 (Bounty Hunter) and 696 (Chicago Cubs Triple Play) were the first two models for sys80B.

I've read on PS that the reset board is often a cause of problems and people often just disconnect it, but if you want a connector for it to attach it to the MPU, I have one. I'll bring it to MGC. I'm running a Swemmer MPU and have no use for it (or the reset board).