May I assume the "ignitor" you're referring to is a points-to-breakerless conversion kit?
If so, the Crane XR700 ignition unit fits (optical sensor). I have one on my '69 with a '67 S distributor (BTW, the only difference is the advance curve). The Pertronix unit should also fit but I have no direct experience with it.
Crane also sells the optical sensor separately in case you want to trigger another ignition box (Crane Hi6, MSD6A/6AL, etc.).
Sherwood Lee
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