Fortune 2 poker machine MPU board issues

[Timber6943]

I have 2 IGT fortune 2 rapid progressive poker machines model 1270C dated 9/85 I currently have problems with both machines. one came without a monitor so I purchased a LCD monitor from Cerionx after battery replacements and some contact cleaning it worked good in one Machine but had problems in the other when you get a winning hand on the first draw the monitor says no signal and goes black until you hit the draw button than it comes back. The old CRT monitor from the other machine worked great in both until the monitor fried the other day. so now the machine the LCD monitor works on has a problem with the door open message. I replaced the optic switch and it tries to reset but always goes back to door open. So I swapped the main boards and the problems moved to the other machine so I'm pretty sure both problems are in the main boards. What I would like to do for now is the swap the chip that controls the monitor so I can get one machine running but I'm having problems getting any info on the boards so I swap out the right chip I have a fortune 2 manual but it doesn't have any info on the boards other than how to replace them it keeps referring me to a 8051 tester manual that I can't seem to find either. The main board Assy. number is 7570190 ser number of 1082
Any help with this problem would be much appreciated