64 Plymouth 273 Intermitent severe misfire.

Hello again folks. This is going to be quite a read so you may want to grab a coffee. I'll try to keep all symptoms and repairs in proper order to avoid confusion. (Wish me luck lol )
I changed plugs and wires last fall because of a rough idle.
I rebuilt the carb in April because of a bad hesitation and it worked beautifully.
I adjusted the valves because they were extremely noisy,a couple were just under .045 thou.
When I was adjusting the valves I noticed a lot of free play while rocking the crank back and forth so I pulled the distributor cap and found a scary amount of crank rotation before the rotor moved. Time for a timing chain and gears.
While I was waiting for the parts I was still driving the car (it's my daily driver in the summer) and one day when I was pulling on to the highway under heavy throttle and just before it shifted into third gear the engine took a nose dive, I thought it stalled but I pumped the throttle and it came back to life and I didn't have the problem again for about 20 miles.
About a week later it started bucking and chugging like it had water in the fuel or at least some kind of fuel problem so I thought I may as well take it to the shop and do the timing set and give it a proper tune up. While I was pulling it onto the hoist it started chugging again so I shut it off and coasted in so I could pull the top of the carb off and see if there was water in the bowl...nothing but pure gas. Shoot, I was hoping that was it.
So I installed the timing set along with intake gaskets, water pump, and points. The rotor was very loose on the shaft but the new one from Rock Auto was wrong so I waited for another. I installed the new rotor and a new cap and took it for a good 30 minute drive on the highway and it worked flawlessly. Got back to town and... CHUG CHUG CHUG. Got a new coil from NAPA... CHUG CHUG CHUG.
Now I'm thinking that maybe it's a voltage problem to the coil so I gave the coil battery voltage and it stopped Chugging!!! But when I removed the 12 volt source it kept running fine so I'm betting it will come back.
Well, that's the story so far. I guess it's not a full cup of coffee story but long enough.
So...what do you think? Thanks, Wally