Engine starting problem.

[Mike_The_Grad]

A little background. 1972 c/10. Rewired with American Autowire Kit about 7 years ago. Honestly had ZERO issues with my truck or the wiring up until a few months ago. Me and a buddy went to have lunch. I start the truck and the starter stays on, continuing to turn the motor over after the ignition kicked in. Made a hell of a noise. Turned it off. Turned the key, engine fires right up. Ignored it, drove to the store to grab a beer. Came out, turned the key, no start. So he tells me to jump the starter terminals with the key in the run position. I do that. Truck fires up. Before I could close the hood hes yelling to pull the battery negative cable. Smoke was billowing out from under the dash. Stinky stuff. Never experienced anything like it. So i crawl under dash and the connector at the igniton switch is melted. Ended up towing it to his house. My other buddy brought me over a spare starter he had. Went to Autozone picked up replacement ignition switch, crimped new connectors on the wires. It literally worked for 2 starts. Then nothing. I had my O.E.M. ignition switch back home. A/c delco made in u.s.a. I installed that. Truck fired up. But every now and then I would have to get out and jump the starter at the terminals. So I checked out the starter which was an original a/c delco. This is for 350 sbc with th350. A couple of the solenoid mounting screws were loose. I tightened them up. I ended up bypassing the neutral safety switch and running a wire directly from the ignition switch down to the starter solenoid. It seemed to fixed the no start issue. However it takes a few turns of the key to get the engine to fire. I mean when I turn the key absolutely nothing from the starter just a click. I got power, lights, stereo blower motor, but nothing fro. The starter. After about 4 or 5 times turning the key the engine will fire. It's been about 3 weeks since I've had to use a screwdriver to jumper the starter. I contacted American Autowire. They are super helpful. The rep ended up selling me a completely new ignition switch. New keys, new tumbler, connectors, terminals and switch. Cost me $40. I installed that last night. Now it seems almost worse than with my a/c delco switch. I dont get it.
I haven't replaced the battery yet.
I haven't replaced the battery cables yet.
I have a ground directly to the cylinder head from battery and obviously positive to starter lug. I also have grounds from engine to frame, core support to battery negative, core support to frame, cab to frame, cab to engine, bed to frame. All connections are clean and tight. Battery is about 5 years old, autozone valucraft(I was on a budget back then) battery about 5 years old. Has 800 CA and 650 CCA. 85 minute reserve. I have brand new powermaster 100 amp alternator(less than a month old) when the truck is on it runs like a top. Volt meter mounted on dash shows 14 amps while cruising. The no start issues dont happen every single time I turn the key. Sometimes fires right up first turn. Sometimes 4 or 5 times. Sometimes first thing in the morning it fires up, sometimes it doesn't. Sometimes when it's hot it fires right up, sometimes it doesn't. I have the starter wrapped in a heat shield and a fabricated thick aluminum heat shield separating it from the headers. I got ceramic coated headers and all wiring is wrapped with fiberglass aluminized woven sheathing. Any ideas??