Upgraded my IIGS Rom 01 with RamKeeper Card with the SlotMover and a GS-RAM Plus 6 meg memory card. Here are some pictures and the brochures. See the Commodore power supply that works for the RamKeeper. I found it recommended in a couple forums. They’re readily available on eBay.
The RamKeeper required it’s own power supply to maintain what was in the ram drive. The above is a Commodore power supply the works.