Not an expert. Ocho Blanco was real nice. I'm unsure what clean really means here in your description. Made many a drink with Hornitos back in the day. Always needed my tequila to be at least 100% Agave . I don't really know how high that sets the bar though.
Either a good tequila or whiskey is...
I dunno what is going on w/ Kohler since somebody scrambled the letters on their stationary. (Rehlko) It seems like they've changed vendors on somethings. Or made one part number to fit multiples. Good idea I guess. Example: Certain carbs now come with a set of pins that I think are throttle arm...
They list a twin cylinder muffler in the IPL, but then for a 46" or 50" model. It's one of this days where they go, hey why not throw a bunch of different stuff in the IPL for your model number...
In addition, verify that saving the wheel is worth the trouble. Myself, I have a homemade puller that pulls from the back of the wheel. Heavy Acme rod as a drive through a hitch bar. It gets them off, but sometimes with such a bang it is scary. If it is worth pulling the wheel, yes.
To me, it would seem there is an issue pulling power @ the starter solenoid. Normally at the same + terminal from the battery on the solenoid, there is a feed off the same lug which goes to a fuse block. Poor supply or a ground for that matter can keep your starter solenoid from actually firing...
So, surging etc. after it has run for 5 minutes? A real simple thing to try is get a few feet of 1/4" fuel line. Drop one end into a small fuel can and the other hook behind the fuel filter. If it doesn't do it, debris is plugging the pick up in the fuel tank.
While I have linked voltage surges etc. to these, I would guess they could be subject to damage from vibration. In fact, sometimes I use the old tap test to get them to fail. The wiring to the module seems decent and I know I've not seen a problem with the harness myself. A better mounting system?
The joy of air cooled engines. At least earlier ones had a tendency to make the breather pump oil if overfilled. It was at a time when Kohler had dipstick changes etc. So, these don't have VC gaskets. . .32-755-49-S should you be so inclined.
Is the top of the block area a possible source? IE...
Well, these are things that you need to know. There is a common like belt used on the X series 48C deck which is just a couple inches longer than the one you require.
Is their oil dripping from the breather hose? These sometimes keeping them slightly under the full level helps. BTW if you suspect the valve covers at all, the composite cover kit is a good way to go.