Cam degreeing help me understand!

How are you trying to find TDC? Use a piston stop. That's the best, most positive way.
I used the dial indicator similar to the video tmm posted i set it up and got it as close to TDC and possible then backed it off about 5 degrees set the dial went up to .25 then back around the other way to .25 the subtracted the difference. It was about 2 degrees off I moved my wheel 2 degrees and did it again and it was just about perfect