this explains how to mod a 2716 eprom to replace the original rom
http://www.nuatari.com/9316to2716.htmlA quick check on an eprom programmer will tell you if your roms are good or bad.
I'll say it again. If you don't know what you are doing, don't work on the boards.
If you stuff the board up working cpu boards are around the $600 mark.
Does the driver board have the sense failure LED on to? Common for these boards to fail as well, hope the flipper relay is OK, these are very expensive and prone to failure.
Joey will work on cpu boards, so you send it there for repair.
http://www.jomac.net.au/index.htm