Ruger MK II mags

[ARG]

Just bought a used MKII target. Both the mags have a red ruger symbol on the baseplate but one is for a MKIII pistol and will not work. It has the piece of metal that sticks out for the mag release button. Anyone in the Tulsa area want to trade this MKIII magazine for a MKII or have any advice how to modify it to work in a MKII.

Thanks
ARG