I've seen others using their CNC mill to route their entire guitar neck, heel included. My challenge is, my hand router based mill with a 1/4" shank diameter seems to be limited to short length router bits. It looks like I would need a 5" overall length bit in order to achieve this. (max height of heel is typicall just shy of 4")

Do I have to convert to a spindle based router setup in order to get a 1/2" shank diameter to achieve my goals?

I've currently created the folllowing MOP to accomplish the heel cutting.