How to read a dwell meter

I have an old anolog dwell meter. It has a switch labled 4/8 cyl - 6 cyl. 
I have an 82 kz305 and a 79 KZ400. The 305 has a set of points for each cylinder, and the 400 has 1 set of points for both cylinders.
Up till now, I have been setting points with a feeler gage, but would like giving this dwell meter a try.
What switch setting should I use, and is there a factor to multiply or divide the readings by?

Mind you, it's been since the '70s,   but IIRC you will have to set it to 4/8 cylinder, and then multiply the reading by 4 for the twins... I think?

Does the 305 have two "single output" coils and the 400 one "double outlet" coil (lost spark)

I actually recently found my old Heathkit automotive tach/dwell meter I built in the seventies.
I would set the proper point gap with the feeler gauges then attach the dwell meter and fiddle around with the knob until you get a dwell reading you can deal with. Reverse engineering, sorta.

Wookie58 wrote:

Does the 305 have two "single output" coils and the 400 one "double outlet" coil (lost spark)

 

Yes, The 305 has two sets of points and two single output coils. It has a 180 crank. When one piston is at TDC the other one is down.
The 400 has one set of points and 1 dual output coil. Pistons move up and down together.

Not sure if this will be of help or not but there are several topics/posts on this subject that a search will reveal.  I found this one to be of interest.
kzrider.com/forum/21-tools/616065-how-to...d-dwell-meter#850216