It's not a slot, its a hole and its not in the right spot, its off by maybe 3/8" if I had to guess.
And more to skwerl's point, sure I/we customize a lot of stuff as needed. I had to grind off part of the side plate to make the outer dogs fit on my new 576 (edit 572), and had to beat the F outta the new fangled bar nuts to make them fit with the dogs. Hard to believe it was necessary-who would run that saw without double dogs?- but I did it to get it done. But I aint gonna bother drilling the F outta a dang bar that it should be child's play for the mftr to make it fit the saw it is advertised to fit.