'76 Duster having bogging and acceleration issues

The title is a little vague, and I apologize; but I have a 1976 Plymouth Duster, stock slant six engine and it's got all the problems that come with a car that's older than Reagan administration.

The primary issue is, a long time ago a group of friends and I (encouraged by a Chilton manual and a significant amount of cheap beer) rebuilt the engine giving us some manner of false confidence. We had space, tools, and equipment at the time that we no longer have. We did the rebuild fine, a dingleball hone of the cylinders, swapped piston rings, crank and cam bearings, timing chain, but left most of the major components as stock. A few hiccups in the form of rusted bolts and studs we replaced but ultimately we got it back together.

Many years later I've had to swap a few other components, namely the ignition coil, the starter, the alternator, and now the distributor cap and spark plug wires. In doing so and in not being told what the proper ignition timing was (it was in fact, not to manual specifications) we had to re-set the engine to TDC and then set the wire and firing order to what was in the manual. In doing so the engine now runs slow and bogs. And when I say it runs slow, at idle it sounds beautiful and starts right up and sings like a sewing machine (it's a .225 from '76, what do you want from it, you know?) but it still has this noise that SOUNDS like knocking, but where-as rod knock stays consistent and gets faster with the RPM, instead it goes away when the engine is at speed and reappears at idling making me think it's a transmission imbalance.

Problem is, I'm dumb and no matter how many videos I watch I still can't figure out a timing light and I FEEL like I can fix this all with just the timing until I can break open that transmission (which is probably almost fried and needs replacing sooner than later), I'm curious if I can two-birds-one-stone this problem and get my power back by fixing the timing.

If someone could explain this like I'm five, I'd be indebted to you in the eyes of every god that could exist. I want to keep this car and not have to sell her, but until I can resto-mod her the way she deserves so she can stay on the road within the confines of the law I need to at least be able to drive around locally. Can someone help in any way that'll let me start to clear 60 miles per hour again?