How do i set the timing on my 1970 Ford Torino Brougham?

Hi there,

I have a 1970 Ford Torino Brougham with a 1974 351C V8 5.8L Engine. I am trying to fix the timing on it because its not running as I know it should. While I'm driving it, it backfires a little bit, and it doesn't accelerate like a muscle car should. I found the TC (Top Center) numbers (degree markings) (10 ATC through 30 BTC)) on the Harmonic Balancer, but i cant find the marker that marks where it currently is (it would be useless to use a Inductive Timing Light without that marker). I've looked online and the recommended degree marking for the engine is 6B (i think that's 6 degrees Before Top Center). BOTTOM LINE, HOW CAN I ADJUST THE TIMING, WHAT CAN I DO WITHOUT THAT MARKER THERE? Please help, if you have further questions or need additional details, please ask.

Thanks in advance!