Ignition Timing Tab

[Bill <Y1TopBanana73@xxxxxxxxx>]

Any reason why the tab for checking ignition timing on my 65? motor
that's in my car and my spare 66 motor would be ~6 degrees different?
The 0 degree mark on my 66 motor tab is at ~6 degrees BTDC on my 65?
motor tab.

What gives? The balancers look identical.

Bill
65 Coronet 500 'vert