Anybody running the '68 4 speed 340 cam?

I've done a bit of work on the engine. I'm getting about 12 1/2" at 20 degrees initial advance at 750 rpm. I sent an email to Ken at Oregon Cam and told him what I was getting and asked him what he thought I should expect with this cam. He said he wasn't surprised with the numbers.
What installed centerline does Ken recommend with that cam?