I think those holes were used to mount a cab on the tractor. Are there also holes in the front of the footboards?
Not sure you can use the 4XX handles on 6" spacing?
I have bought a used tool box off a JD425 parts tractor thinking I would put it into the fender of my 322 as I did the grab handles. It looks like the box has a slight bow to its surface. Will it fit flat on my fender?