yeah ... I dont think that is right... . Buddy installed a diesel in his 4runner. . passed with no issues. last year I installed a gas motor in an older diesel rabbit years ago. . passed with no issues.
Worst case scenario assuming no check engine light in a OBDII car is they snap test it. I have actually had a OBDI car pass with the light on seeing as there is no emmissions on the OBDI computer...
My advice would be to call and speak to someone at the emmision station but my experiance has been positive there. . even in a 87 Unimog... no OBD, no cig lighter... just a probe in the tail pipe