You are almost always better off with the part numbers from the ROM chips, than you would be with the part numbers from the circuit boards, as Charlieman pointed out.

This is particularly apparent in the case of the Beige G3. OWC tried to compose a web page which would guide one to identifying the ROM revision of Beige G3 ROMs based on circuit board markings, but there are so many exceptions, it is nearly useless.

There are three revisions of the ROM chips, which all go in the same type of chip and those chips can go on any of the circuit board revisions. So the only association between ROM revision and circuit board revision is caused by overlaps in manufacturing dates.

Similarly, with the Macintosh II family ROM SIMMs (including the SE/30) the circuit board can be the same for all models. In every Mac II model which uses a ROM SIMM, the SIMM is a 64 pin SIMM which plugs into the same type of socket used by the IIfx RAM.

There are several SIMM ROM designs because Apple used several differently packaged ROM chips and so needed circuit boards for each type of chip which they wished to mount.

By the time of the IIfx Apple seems to have settled on the 32 pin PLCC chip for their ROMs.

Anyway, any time you wish to identify Apple ROMs, your best bet is to take the Apple part numbers off of the ROM chips themselves.