Piston Stop Advice

I prefer not to use tape. Just measure carefully around your balancer with a light flexible tape, ACCURATELY, and figure how many "degrees per inch." Then figure how many inches for say, 40*. Mark that off with your tape, carefully, and double check your measurements.

Then you can use dividers to mark that in half for 20*, and with the dividers duplicate the 40 and 20 dimension and mark out to 60* for vacuum advance. Then divide the 20* marks in half to 10, and if you want, to 5*. Use a small square and a scribe. Doesn't take all that long.

Crackback doesn't even do that -- just uses a hunk of masking tape and makes a temp mark to get timing set.