I don't see any indication on the holes that you have worked on them, but rather it appears you were trying to remove the freewheel by hammering on the removal flats! If the freewheel is not to be saved you need to disassemble by using a small strong punch or an old screwdriver small enough to fit into the holes on the faceplate and work clockwise. Be ready with a large rag or bucket underneath to catch the 1/8 inch ball bearings. When the top cone is off just lift the freehweel off, get rid of all the bearings and remove the pawls. you then should be able to put the remainder of the body in a vise (clamping where the pawls used to be) and turn it off counterclockwise.
p.s. You may have to do the above even with your modification to the other freewheel tool, which was unwise, as the grinding could compromise the strength of the tool and can't be as accurate as using an original. More importantly the very old Suntours had a raised ridge above the faceplate instead of the removal slot being completely enclosed. That makes for a chancy removal with anything but a centered, well-fit tool, firmly tightened down with the skewer. If you are able to use the remover be sure to loosen the skewer as soon as the freewheel breaks free.
Last edited by cny-bikeman; 10-30-12 at 08:36 AM.