Welcome back:
It could be the switch or a wiring issue from the switch. Now for the nightmare. The power lead to the distributor needs traced to see if it is damaged, disconnected, and has continuity. If the wire is good and make contact where it should, then suspect the switch.
I wish I had a wiring schematic for you, but even if I did, someone modified the car and it wouldn't be right. And yes, since the power doesn't seem constant, either you have a weak connection, bad switch (that can't handle the power anymore), or even the wire to the distributor can be broken internally (under the insulation). You may want to just replace the wire to see if power then stays constant.
Let me know if you have other questions or need help.
Joe
Sunday, July 7th, 2019 AT 7:19 PM