The masks on this board were all Fujitsu MB834200B chips, which are pin compatible with 27C400 EPROMs so dumping them was easy enough. Five out of the eight were fine, number 2 had a blown /CE pin, while 6 and 8 were utterly wrecked. Removing all 3 from the board also removed all the rubbish from the screen, leaving nice clean jail bars behind.