Transferring N64 cartridge savegames to a 64drive / everdrive 64

I built some simple custom hardware and wrote a little savegame dumper to back up your 4K/16K EEPROM based N64 savegames to your cartridge emulator.

The details for the hardware can be found here http://themanbehindcurtain.blogspot.de/2013/08/transferring-n64-cartridge-savegames-to.html
and for the custom dumper software here http://themanbehindcurtain.blogspot.de/2013/08/transferring-n64-cartridge-savegames-to_16.html

I own a 64drive but I guess this should also work for the Everdrive 64.

Currently there is only 4K and 16K EEPROM support.

I already wrote the software routines for SRAM / FLASHRAM copy,
but I am not sure if it is even possible to hook up the SRAM/ FlashRAM without desoldering.

I guess the following PINs should be mirrored: AD0-AD15, ALE_L, ALE_H, VCC, GND, \read, \write
Switching is not really an option because the dumper is still running from the cartridge emulator,
but mirroring is also problematic because the game PROM in the cartridge will most likely react on the read requests.

Desoldering the SRAM is also no option, because it will loose its content after power cut.

So the only option I am currently seeing is desoldering the PROM or cutting its VCC pins (resoldering afterwards of course) with the following process:
Start dumper, disable savegame emulation on runtime (so the virtual SRAM, FlashRAM will not respond to our read requests), connect VCC from the external cartridge,
read complete SRAM / FlashRam into memory, disconnect VCC from external cartridge, re-enable correct savegame emulation by cartridge emulator and write memory content to virtual SRAM / FlashRAM.

I am not really satisfied with this solution, because i actually don't want to desolder every N64 cartridge. So has anyone some thoughts on this and maybe has a better (less destructive) idea ?
Help would be greatly appreciated.