Modification to the foot of Nikon's SG-3IR so that it can be used on Canon's 7D, 60D or 600D.
A really sharp knife, perhaps with a slightly scalloped edge, would be the perfect weapon. Clamp the foot in a vice using a cloth to avoid marking. Sit down and control both ends of the cutting blade as precision is required. I started with the long cut, leaving it incomplete - then made the oblique cut - then finishing the long cut. Finally, I thinned the tab slightly, cutting a little from its lower surface. Think twice & cut once!
As shown, works perfectly.