Here's the Amberola 30 Dataplate Series 3 Dataplate location...
See Attached pic below:
Note: As these Amberola 30 Machines were being made, when they went from one series to another, certain parts (Including Dataplates and their locations) did overlap in production such as different types of lids (Yes, There were at least two different types), other small parts and so on. The "Dataplates" themselves also evolved and three to possibly 4 different types of "Dataplates" have been noted and observed as well. Nothing is etched in stone, This is just a "General" guide.
Tony K.
Edison Collector/Restorer