1960 Harmonic balancer pulley

[79Square]

I am adding power steering to my 1960 C10. It has a 6 cyl 235. I got a conversion kit with a special power steering pump and alternator bracket from Performance Online. I am adding a double groove pulley for both the power steering pump and the water pump. My problem is the harmonic balancer pulley. The stock balancer has a single pulley that is riveted and will not allow any 3 bolt pulley add ons.

Does anyone have any suggestions on how to add a pulleys to the stock harmonic balancer or will I need an new one. If I need a new one, any suggestions on where to get one.

Thank you.