As long as the rotor is contacting the number one terminal on the cap i dont see where it would matter.. Mine is around 11:00 I think.. You can loosen the clamp on the bottom and fine tune it. Here is a link out of the service manual for installation

Distributor Installation

Last edited by 1953redchevy; 01/12/2012 3:56 AM.

Daniel

1953 Chevrolet 3800 Stepside