[Foot Stomper]

Start with the basics, not fuel related because most times rough run is electrical and not fuel...most times. If you can rule out bad fuel then look to ignition. Working carbs never just go sideways!

Start by confirming timing, timing advance, points and condenser next, then coil. Coils can (and do) fail under load. Then wires and cap/rotor and then plugs.

I had a condenser fail on me and chased that pr!ck for awhile!

Don't worry about muffler bearings, flux capacitor or blinker fluid, stick with a solid electrical diagnostic and I'm sure you will find and solve your problem.