Nissan Repair: defective part in ignition or charging system, 1986 nissan 300z, dash lights

Question
Hello,
I have a 1986 nissan 300z that has a electrical problem somewhere. The car will be driving fine and then all the dash warning lights will come on the alt meter goes down to 10-12. I just replaced the alternator because I thought that might be the problem, but it's still doing it. I had the battery tested and it's fine. When the dash lights go off, it starts charging again as normal.

Answer
There is a transformer on the instrument panel and that is what I think is going out.  I had a 280Z with a similar problem.  Even with the warning lights on the car still ran fine.  But all the lights and gauges went nuts.  I changed the regulator on the back of the instrument panel and all was well again.  I bought a instrument cluster from the wrecking yard because Nissan wanted something like $100 bucks for thei little regulator.  I bought the instrument panel for $50 bucks and got to keep all the spare parts for the next time.