I bought a new timing light today. First time I have ever used one. The instructions are simple enough so, I hooked it up and started the engine. First check of the mark showed ATDC way above the tabs, so I advanced it a little, rechecked 2 degrees ATDC. If I'm not mistaken, should'nt the initial advance for SBC be somewhere between 10-12 BTDC??? I cant get there. The vacuum advance unit is against the intake runner and only showing about 3 degrees BTDC?? This is with the vacuum disconnected and plugged of course, but something is not right here. WTF?? I'm stumped!!! I knew this thing wasnt running right, getting too hot at times thats why I bought the timing light, and it was WAY off. HELP!!!!