[Hoop]

Your timing is set at 19 degrees BTDC ... CRANKSHAFT degrees. On the distributor, that's 9 1/2 degrees advance since the crankshaft turns 2X the distributor.

The objective is to eliminate that 9 1/2 degrees of advance at the distributor.

You do this by adjusting the rotor just like you do all Model A timing.

Set the timing as you would a Model A. Make a mark to reference where the rotor lines up to the distributor body. Make another mark 5/16" on the body in the OPPOSITE direction of the rotor's rotation. Move the rotor (pin is still in place and engine does not turn at any time) to line up with the new mark and tighten it down.

(Do the math on the circumference of the distributor and you can convert the degrees to inches.)

This causes the rotor to arrive at the firing point later ... retarding that 9 1/2 degree advance (19 degrees at the crankshaft) and giving you 0 degrees of advance.