One of the most common problems for the M30 is the passenger side vent. It is often found broke or breaks… whether it is the outer bezel or the part holding the fins… something breaks.
Additionally, getting a replacement is difficult stateside. Many dealerships don’t have.
What some of the M30 owner in Japan have done is get the R31 skyline vent. Since the M30 uses the same dash (just reversed), the vent works.
Again, thanks to Satoshi for doing some research. The R31 skyline vent is the same as the M30 vent as far as part numbers.
There is a slight color difference… but it is not too noticeable.