Here's something I just noticed. So at 18,19,31,&36 I have 27c301 (hitachi). At 30 I have M5M27c100k (mitsubishi) an at 35 I have D27C1000D (NEC)
My 2 chips I have tried are as follows:
MX27C1000DC (Macronix) & NM27C010Q (National Semi). I based this choice on the Final Fight board pictured in the A board thread having AM27C010
What stands out to me is that the Output enable is on pin 2 on the original chips, but is on pin 24 on my selections. Could this be the cause?
*edit based on your info I looked at the link and it looks like my chips are non-JEDEC, and I bought JEDEC chips
I bought some 27c301 hitachi chips to try.