Pretty sad and frustrating, but it happens all the time with new guys. I don't know why. They ask for help and then go to sleep. If you are too busy, don't ask for help until you are not too busy.
1. Ignition problems= not specific. I assume "I get nothing" means no grinding no noise no clicking no buzzing.......
2. Voltage regulator has nothing to do with cranking
3. Alternator has nothing to do with cranking (you must have an externally regulated alternator) You say battery is fine.
4. "Battery is fine". With what you have said so far, you are not experienced in electrical, so how do you know battery is "fine"? Did you test it?
5. Jump the starter down at the solenoid. This will bypass the ignition switch and some wiring. It will isolate to the solenoid, starter and battery cables (if battery is actually "fine"). I doubt it.
6. Your 66 GMC 305 V6 starting system is no different than a Chevy. No shims. No nothing special.
7. Please provide the solenoid part number, where you got it and a picture, or careful statement, of how you wired it.
Right now you have a "no crank" situation. We don't know what you had when you decided you needed a new starter solenoid. You called it "ignition problems". We are glad to help you but don't analyze the issue, or give it a name, just state what the motor is doing or not doing. We will ask specific questions and get you fixed. Provided you have not fallen off the edge of the earth and have no computer service.
It's good, especially when new to a forum, to monitor your own post because you have good folks taking the time to help.
I don't know if you can post pics while moderated. Stay safe, See you next year.
