put the + and - clips onto the coil , it is marked with a +. make sure you are reading the correct scale on the meter, start the car. It will tell you the dwell.

gap is inverse to dwell angle number. bigger gap = lower number.

the dwell angle is the way to set the points, you may not get the gap and angle to align due to wear on the points. Set it to the correct angle, then check your ignition timing with a strobe gun.