Well, I have lost the original post while I was away visiting
inlaws but here is my suggestion to the guy who was having
trouble getting a steady idle:
The last post I saw, he mentioned that the PO had converted
to negative ground. Check the polarity of the coil. Believe it
or not, you do get a better spark, at a lower voltageif the voltage at
the spark plug terminal is negative. According to an article
in the tech tips from the Carolinas Area Austin-Healey Club,
this is because the center electrode on the spark plug gets
hotter than the side electrode. Electrons will jump the gap
more easily from a hotter electrode.
If the coil has the terminals marked + and -, the - terminal
should be connected to the wire which goes to the points.
Hope this helps,
1963 Austin-Healey Mk II