Generator questions
 

I bought an older Onan 4.0 BFA and converted it to propane for my toter build. it produces power but bounces between 122.x to 123.x. Is this ok? Is there a simple filter/regulator/inverter solution to make it a clean steady power?

Also, my m2 has only one stack and was thinking of adding another stack and piping my generator to that stack so that it would look better with dual stacks (my opinion) and serve a purpose since it would be raising my exhaust to above the roofline of my rig. We plan to use the generator as we travel along while camping/boondocking. The truck will be pulling a large horse trailer with horses so the exhaust being above the rig seems to be more desirable but maybe not necessary.

Any advice?

The stack idea sounds like a win just have a look at the RV ventury exhaust as you might have to keep the bottom area of the stack open [obviously it could be hidden under the truck]

As far a gen set...most gen power is not really clean so it causes certain issues with electronics etc....how bad it is, not sure as i'm not a generator tech, sorry.

Not sure on the oscillation, maybe governor adjustment?
On the power end, just get a good UPS. Kinda heavy but will protect your pc

Ignore the voltage fluctuation. Put a volt meter in your kitchen outlet and hit the toaster. Voltages vary.