Also remember that that flange that needs to be removed is a counter weight and will affect the balance of the crank. Most aftermarket crankshafts have a round flange and all of the shorter stroke cranks like a 283 or a small journal 327 also had a round flange. Longer the stroke or heavier the rotating assembley the more counter weight and or heavy metal needs to be added to the counterweight approximately 180 degrees from the rod throw. If you are lucky the crank has balance holes in the rear counter weight that can be filled with a steel slug and welded in, if not you will have to add heavy metal in the rear counter weight installed sideways in the counterweight.