I'll post a few pics of the jig I'm designing. The job could also be done by standing the block up on the base of a floor mount drill press for more precise control of the cut. Both sides of the web will need to be cut to preserve the alignment of the timing gears. It has a 1 1/4" shaft, and runs in ball bearings centered up in the #2 and #4 bearing saddles. I bought the side milling cutter on Ebay. The depth of cut will be controlled by a shaft collar clamped to the shaft. "Designed and built by R. Goldberg"!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!