Does anyone know a rig where the pedal plate can be swapped quickly?
Might something like this work? With a screw through each of the mounting holes the pedals could be 'dropped' into the rig easily enough and that should keep them in position. If you can get hold of wingnuts similar to the one pictured they can be fastened without much faff, and I doubt you'd need all 6-8 of them. Might even get away with two at the front of the pedal plate so it doesn't lift when you stand on them.