Ditto the tape, used the 1" variety because it was handy to get the proper spacing.
My method was a little different - block wheels, drop rear driveshaft (duh), then MAKE SURE IT'S IN 2 WHEEL DRIVE, start the motor and drop in gear (I remember reverse). I used a 4 1/2" right angle grinder with a cutting disc and a mark one eyeball to get the cut square and concentric. To get the bolt hole drilled square to the world, I started with a small bit in a cordless drill, output shaft still spinning, and went to town. The spinning stub shaft will automatically center the hole, if you hold the drill near the center - the hole may not be the eact size, but it will be square to the shaft. Turn off the motor, set in park, drill out to proper size in one or two steps, the tap. Use plenty of oil!!!
I then restarted the motor, ran forward, then reverse, while holding a small stone to the edges to knock off any burrs and create a small chamfer on the edges. HTH, Cheropair