>They used a Mortal Kombat 4 U76 PIC16C57 as a replacement for #139 Invasion U76
Any progress towards getting pcbs fully preserved (still be repairable in future years) and the Midway Zeus hardware titles eventually emulated is a good thing. Odd that the mcu was documented in only one of the games and left off the others at this time....assuming the remaining (not mentioned) games from Zeus hardware also use that chip.