440 Harmonic Balancer Timing Marks Off

You need to STOP, degree the cam and then verify TDC.

Edelbrock did NOT say to not degree the cam. They said don't move the intake centerline from to what they say it should be. Even that is stupid (on edelbrocks part) but at this point, you don't have any idea where the cam is installed.

Once you have verified TDC (not on the damper but TDC itself) and have the cam degreed then you can check TDC on the damper. The two are unrelated but you still need to check the cam.