Timing Mark Indicator

[Notadufus]

My '49 8BA has a timing pointer and a dot on the wide rim at the rear of the crankshaft pulley, but I'm not sure how to mark the degrees of the pulley. (Like what is the distance between "0" and "5" degrees?) I have a Chevy distributor and need to ensure the advance doesn't go over about 24 degrees.

Apparently, no one makes adhesive timing pulley tapes, anymore.

Does anyone know the circumference of a '49 V-8 F-1 pulley? Mine is in a place that's difficult to measure.