I ordered new points/condensers for my 550. Now when I go and put the timing light on it, when do I want the the mark to line up with the "F"? Idle? And at what rpm do you align with what marks. I know there is a "t" for TDC and a "f" for what I am told is 5 degrees BTDC. This is my first time doing this myself and my manual of course tells me to take it to a dealer for this setup. So a little crash course on this would be great. 78' 550k by the way.