Doubtful. Most likely done with what's called a Rotary Broach.No I am waiting from someone I know that has as cnc shop
He made me an a pto to swap a CMB on an OS but that's alot easier
Why can you get any print?
I'm guessing the female hex was done by forge or cast die
Outside my knowledge
The problem with a rotary broach is the cost ..... they are very expensive...It was done with a broach, Jerry said Miller Agnew brought one over from the UK and it made the hex hole in the PTO. Mike
Get 1/4" steel "HEX" stock..... result= hex into lower unit and square into K&B PTOI think the best way is get 3/16 round stock maybe 4140 cut to length and mill the square end for the stock KB pto
If you go with the hex you will have to change the PTO bearing due to a larger pto shaft due to the hex.