Im working on a tri zone for a friend and i have an issue i cant figure out. It has a rottendog williams 3,4,6 mpu driver combo in it. When you start a game, the bottom pop bumper and the left sling coils lock on until the fuse blows. I replaced the q6 and q8 transistors on the mpu (im assuming the designation is the same on the rottendog board as the original but i do not know). And it still locks on. I feel like im missing something easy and i cant figure out what it is. The gaps look good on the switches, diodes look good, etc. Any help would be great, or a schematic for that rottendog board, its the older version that doesnt include system 7. Thanks!