Most Roland serial numbers have a 7 digit designation containing 1-2 letters and 5-6 numbers.
The serial number can be found on a white sticker on the bottom or back panel of the product.
For some reason, I thought it was newer than that, but now I know.
My reverb unit says:" Manufactured by beautiful girls in Milton, Wis.
The first two digits are the month of manufacture, where month 01 was September 1972.
The remaining four digits indicate how many of that model had been produced.
With certain battery powered products, this sticker can be found in the battery compartment.
They can also be located on the UPC sticker on the outside of the product box.