1. The starter mounted switch is not a solenoid switch as you say. It's not called that by anybody including the vendors we use.
2. You don't need anything but a 12 or 21 circuit, pre wired fuse panel, universal harness kit. ~ $185/$205
3. Your ignition switch could have ON and ACC separated inside switch, but many are "all terminals are off or all are on". Continuity test will show.
4. Your charging systen, whatever you have or decide to do, has nothing to do with your ignition/starting circuits.
5. You mention a bunch of electrical ideas/components/wiring that are not needed, if I read correctly.
6. As far as wires/fuses for "dials". Depends on if you have mechanical oil pressure and temp sensor (tubes instead of wires). The gas gauge and ammeter are electrical.
7. You are right about ripping out old and starting with new.
8. As far as alternator vs generator, don't worry about that. Very easy to change to alternator. Way less wires.
9. If you buy the 12 circuit or 21 circuit kit, all things will wire up, no sweat.
10. As Kevin posted, Kenneth will have you covered with parts, rebuild service and advise.
In case it needs clarified, your ignition is wired: *
1. Wire from Ign SW to one side of ballast resistor.
2. Other side of ballast resistor to coil positive.
3. Wire from starter mounted switch side terminal to coil positve
* (if coil is an externally resisted model)
