Hey Dennis,
I would make a custom Macro code to do it, if it is a lot of identical repetitive holes. I would make a "Wizard" for it. I would put this code in the place you want The Drill to start.
i.e. M300
After your drill G83 or what ever is done in the code, and the Z retracts up to your rapid plane, I would place my macro to follow it.
If using a "Wizard" above, you could auto insert the M300 after any drill cycle type.
'Drill-Counter bore macro M300
' ActivateSignal(OUTPUTx) '(use some output to flip the air logic to move the drill up, and mill down or whatever)
Code "G91 G 00 X -6.0" ' lets say the the Mill head is 6 inches to the left of the drill head OR, use G55 for fixture offset, or G10
' ActivateSignal(OUTPUTy) '(or use here if at this point you need to flip up or down one or the other heads)
'IsSignal(INPUTx) '(optional you could use some inputs for error checking to make sure the flip occured, perhaps a If-then
'statement that sends a message.
Scott