Thanks for the advice so far....after some research on this site, I've discovered that the cdi box is actually a permatune...so no noise.
The permatune is getting 12 volts when the ignition is on, and after doing the bench tests suggested in this thread
http://forums.pelicanparts.com/showthread.php?t=364174&highlight=test+cdi it passes.
I've also tested continuity on the wires from the permatune to the distributor and coil - both OK.
Points look good.....no corrosion and adjusted correctly.
Bench tested the coil and seems to be ok - I'll check the coil installed later on today when I have a helper.....