Ah, code 67 with the clutch in or out means a bit of a wiring nightmare. You've got a bit of troubleshooting ahead. If the car has been rewired with the painless kit, it's quite possible it's missing a few key wires, specifically in this case, the neutral gear circuit loop. Are the two plugs near the clutch pedal hooked up?
Was this car originally an automatic? Now it's a 5-spd?
Automatic and 5-spd cars are wired very differently here, so really need to know what you have. It's a 1991 chassis, originally a 2.3L. What trans? What ECU are you running?