Hopefully it’s the fuse under your seat

"No power to anything" might need clarification. 

First thing I'd check is the fuse. 

Probably be lucky & just the fuse under the seat although woulda thought it'd blow quicker than time for a Boom. If that doesn't fix it look under the regulator for results of something bad.

Alright so it was a fuse-never recognized that was there and there was actually a spare there. Boy do I feel lucky. Changed out the fuse and the lights are back on. Thanks for the help-will probably need to get some spares.

So now after swapping out the brushes and the fuse and still no spark. Now it seems there's no spark at the plug wire where it was there previously.

Some of these 50 years old wires have a pretty weak connections and by pulling them off to change the brushes I probably loosened something. I'm thinking next steps would be to solder the wires from the harness to the connectors and use shrink wrap over them. 

From there I'm guessing new points wouldn't be a bad idea. I actually have a spare starter and NOS starter switch assembly from a long time ago, but want to troubleshoot before I swap out so many parts I can't figure out where it's breaking.
 

Spark is super simple on that model.  Battery ignition.  No need to crank engine.  Key on, points closed, carefully open points with small screwdriver.  When points open, you should get a spark. 

With points open, you should have 12v at points wire.  A simple test light can troubleshoot very easily. 

Need to make sure battery is charged and connected though, no spark without battery on that model.

Could just run 12 into the coil direct & other side goes to the points. Has to spark then, unless there's a disconnect down to the points. Probably even spark [but not concentrated] if you flicked the coil points wire [disconnected] across an earth [at the coil or close by].

Thanks for the tips! I was able to troubleshoot it a bit, and it ended up being a loosely connected wire. So the fix was brushes, filing the points, and fixing connections. I have spark now finally.

So I figure while I'm on electrical troubleshooting, I have spark with both the kick starter and the estart, but in the past the estart never worked to start the engine but I think it did have spark.

What's the weak point of the at3 estart that typically goes bad? I would think spark=functional estart but I'm pretty sure I had spark when doing some troubleshooting a long time ago and the estart never worked.

It might be confusing because all the parts are located in that one place. 

It's no different than a car though...  the points are for the ignition system. 

There is a generator to charge the battery.

There is a starter motor to start the bike. 

Starter and generator share the same armature... 

You could disconnect the starter and the generator would still work...  you could disconnect the starter and the generator would still work.  You could disconnect the starter and generator and the ignition would still work (until battery went dead).

Any of the 3 systems will work on their own...  of course if you don't have ignition you'd have to find a way to spin the generator to make power. 

Does your engine turn over using the estart or is it turning over slowly or not at all