Yeah, pulling the light sensor might fix it. I had to do that on a '97 Cadillac I used to have. The sensor went wonky and it would go into DRL mode, regardless of how dark it was outside, which meant I didn't have dash lights. Once I pulled the sensor, it worked just fine as a manual system.
Isn't there a problem with the plastic plenum and a turbo? It seems like guys do aluminum so I always assumed they flexed too much for boost and leaked.
I don't know for sure.
That car looks really good, hope you make it to a meet some time.