Electrical knowledge needed

By "starter solenoid" I think you mean "starter relay." If you want to hide it you can move it under the dash, or replace it (under the dash) with a modern "Bosch style" which is what is used on the Ram/ Dakotas, etc.

So far as the ballast follow the destructions pertaining to whatever ignition system you install. If you DO eliminate the ballast, there is one "catch." The IGN1 "ignition run" output from the ignition switch feeds out into the engine bay, feeds one end of the ballast, the VR, the alternator field, electric choke "if used" and some smog doo dads, depending on year/ model. THAT FEED GOES DEAD during crank

The ignition power for "start" comes from a SECOND contact on the ignition switch, IGN2, which is the (usually brown) ballast bypass circuit. This comes from the switch, and goes to the coil+ side of the ballast, so the coil gets full battery voltage during crank

If you install any ignition NOT using a ballast, you either need to connect the ballast wires together or connect the IGN1 and IGN2 together.