7 1/4 to 8 1/4 Swap

You can oblong the holes in the 7 1/4 shock plates to work
Can you actually oblong the holes? With the way that the shock mount is set up it looks like it might require some grinding or a lot of shims to be able to make that work. A guy at my local machine shop (who now that I think about it, might not actually work there) said that he doesn't know of a way to oblong those holes besides a CNC machine. I should've just ignored him and talked to the guy that was actually going to do the machining. But y'all are saying its possible to get through the 1/4 inch thick steel?