Ta - do they have a magnified live view too? (Sorry Gary )
Getting back on track, you might look into the adapters with built in iris for aperture control of the EF lenses. Like this:
Also it allows you to use the cheaper extension tubes for macro photography.
Just search the auction site for EOS micro 4/3 iris adapter.
I would be weary to use these. In any lens the location of the diaphragm is critical, an add-on diaphragm is certainly not located optimally for any complex lens you might be using.