I just installed the Rally Dash cluster in my 140 over the weekend. I was told when I got it that the Gas and Temp gauges didn't work, so I replaced the regulator (that silver bolt-on metal component on the circut board) with a known good one from my old stock dash (they look identical). Well, after connecting it up, everything worked except the Gas & Temp gauges and the back lighting. I verified the bulbs were good by hooking up jumpers directly to the battery and the lights worked, but they don't when it's installed to the connectors in the car (and turning the headlights on). Looking at the circut board visually I don't see anything wrong. Any ideas what I can try to test or fix it?

If I'm not able to fix it, does anyone have a spare cluster with a good circuit board? I don't need the tach or speedo, they work fine. I'd even consider sending it to someone and pay to have it repaired if necessary. Any help is appreciated.

Here is a picture of the back of this gauge cluster: