You can cut that blade down quick and easy with just an ordinary saw file. Mark the spot you want to cut it with a Mr Sharpie and then start filing a channel with the corner of your saw file along your line. Go about 1/3 of the way into the plate, which isn't much, maybe .010 or so. Then put the waste side in a vise with the channel just above the jaw and bend the saw away from the channel. Wear safety glasses and a pair of gloves. Typically it will snap cleanly right at the line. You can then clean it up with a mill file and round the toe as it was before. That's the way I used to do it back in the old days before I had a dedicated shear.