Yeah, that's one issue you don't have to deal with for internally modded controllers, which was part of the reason I originally chose to do internal mods for the SNES controllers. Unfortunately, it's far more difficult sourcing OEM GC controllers in good condition (at least consistently so... Ebay's always a gamble) than it is to find GC extension cables. So yeah, just always have the GC controller plugged into the adapter before you plug it in to the Wiimote, and always unplug from the Wiimote before unplugging the GC controller.