Generally, the narrow pickup seems more common in earlier guitars, and the wider pickup is common with the later models.
I had been exchanging emails with GR-user Jonathan Prince, who had, once upon a time, ordered a replacement hex pickup from Roland. Mark Wire, it lays out all the technical information on the pickups that I had only surmised!
The cards are labeled as version "A." The published Roland documentation supports version "B: and "C." These rare "A" cards are unusual in several ways: the component layout is very different and the outputs trimmers seem to be arbitrarily placed on the board.
You can also see jumper wires soldered across the board.
The other vintage controllers, the G-202 and G-505, are well-built, fine guitars.
But they cannot escape the feel of being really well made Fender copies, no matter how nice they are. The more expensive G-808 has through-neck construction and other nice features, like gold hardware.He mentioned he had misplaced the paper they sent with the pickup explaining what parts to replace when he installed the new pickup. View the original note from Roland sent to Jonathan Prince. But Mark Wire was able to find a replacement hex divided pickup! 413100 Mark goes on to outline the resistors that need to be changed for the new #610 pickup.I emailed back that his memory was probably fooling him, as there was no official Roland documentation on the pickup change. "We don’t have any humbucking pickups for your G-808 (I physically went out to parts dept. And Mark notes the serial numbers of the new and old pickups: Old type: #601 Pick-Up 22380601 New type: #610 Pick-Up 22380610. As it turns out, these are exactly the modifications that I outline in the notes below.Also, vintage guitar synth guru Rich Hilleman has suggested that the through-neck design of the G-808 adds to the resonance of the guitar, making the G-808 less suitable as a synth controller.I have tested and played both guitars, and can not say that I was able to detect a difference.One pickup is small, with an impedance of 80 ohms, and the other pickup is slightly larger, with an impedance of around 900 ohms.For my purposes, I labeled these pickups as "wide" or "narrow." One pickup is around 10 mm wide, and the other is about 12 mm wide.Mark lists the serial numbers of guitars that use the older style, #601 (or part number 22380601) divided pickups: G-202 before serial no. For the G-303, G-505 and G-808, each string needs two resistors changed, one effecting the synthesizer signal, and the other effecting the hex fuzz signal.The G-202 has a different hex fuzz circuit, so only six resistors need to be changed.In addition, the standard 1/4” output jack solders directly to the PCB, rather than the ribbon connector.The first time I tried to repair a failed op-amp in a G-303, I realized that the pin-out documentation was wrong on the schematic.