First time troubleshooting something like this so I appreciate the help. I've measured voltage at the bulb locations in that row and all of them read in the mV. When I measure across CN6 and CN7 connector pins for the return and drive for that row, I get 7 volts. I've measured across other pins on those two connectors when that Row is active and I get about the same voltage.

Also, none of the lights work when testing them in their columns either.

Is this telling me that I have a shorted/open conductor somewhere before the first light in that row? And would that be LB5 according to the manual?

Thanks again.

A broken diode on a single light shouldn't effect and entire row though should it, being wired in parallel?

I'm pretty sure that they worked 'before', I specifically remember seeing the egg light, which is in that same row. Guess I'll just follow the row wiring and see what happens, I was hoping to be more scientific about it.

Well, I was trying to give some measurements that might lead me in the right direction, to me, it seems the drive and return right off the CPU board is fine...that would be a nice confirmation.

Yes, it's row 5 in the light matrix, I know what color it is. I've used a continuity tester from the CN6 connector for row 5's return all the way to the last light in that string, which happens to be the T-Rex Map light on the Shoot T-Rex indicator (T-Rex Map light is also on the playfield) and measures continuity all the way.

Looking like the transistor for that row, I'll try to test that with a diode tester, but it's tough to get to.

EDIT:
Q76
Red Lead on Base
Emitter = .569
Collector = .501

Black Lead on Base
Emitter = .934
Collector = OL

Does that look like the transistor is bad, you shouldn't pass current with the black lead on the base on either the emitter or collector right? This is all in circuit testing, so does that make a difference?