If you Have spark at the coil big wire to a ground when cranking then the Pertonix Is electronically making and breaking the connections between the smaller Neg. and pos. at the coil.
That is all it does and replaces exactly what points do.
When the spark comes out of the coil it is directed back to the distributor cap where the rotor makes the connections to the correct plugs as it turns.
Tells me you have a problem with the dist. cap or the rotor.
Check the button (spring loaded in the dist, cap center) or a broken or not turning rotor (broken idexing lug inside rotor?)
Things to check.
Happy hunting, does not sound to hard- hope!
DJ