sounds like its not complied man, the mod plate may have something to do with engine changes or the sort. My NSW complance plates are like 2 green plates rivited into the engine bay, near where the build plate is.
Depends when it was complied.
Different years had different rules.
I had an 83 Supra that had NO compliance plates on it. Must have been imported pre-1990
I have an 84 Soarer that has a green plate on it, and a NEW number stamped on the strut tower. It was complianced in 1992.