Reply by sprucegum

I milled out the top using my old jet drill & mill , had to reposition it on the milling table a couple of times as I did not have enough travel to do it with one setup . I don’ think it would cost too much to have it done, pretty simple job, a machine shop would do it in less than half of the time it took me.

-- A tube of calk and a gallon of paint will make a carpenter what he ain't