[Bluebell]

Pertronix does one for the 42-46 distributors. It (the reluctor) replaces the points and does away with the condensor. It comes on a base plate that adjusts the timing with the screw in the side, exactly as standard. The base plate comes with a new bush to support the rotor end of the shaft.
The down side is that you need two other things:
1. The correct coil to go with it.
2. a set of new ht leads that are not copper wire type. I believe this applies to ALL electronic systems.
I bought the first type reluctor (a mistake) The PertronixII has protection that prevents the unit from burning out if the key is left on.

I am lead to believe that this is a good option, more so if your cam is not in good condition.
None of this makes any difference if your advance components and vacuum brake are not up to spec.
If you are ever welding on any vehicle, it is good practice to disconnect the battery.
I hope that helps.