I inherited a 1982 Cadillac Eldorado Biarritz and the Check Engine light stays on (idle rough, no fuel gauge readout, other issues).  I had it to the dealership and they checked it, found that it had already beed replaced with a different computer for Cadillac Deville.  I got the right computer and things ran better, and actually tries to run diagnostics (but fails to finish, also can never retrieve the error codes) but I had to use the old deville roms, because I cannot find a place for replacements.  Does anyone know where I can get a set of roms for this old car?  (Or a place to make anything custom for it) It has the 4100HT Engine, but I just need places to call.  I tried dozens of places and no one knows.  Thank you!