If you have no air leaks, the throttle plate is closing all the way, and you can only obtain a good idle by adjusting the low needle, by all means do so. Don't worry if you are a tad rich (especially on the low) it is not going to hurt anything.

By the way, what do you mean you can not find good gas or lube?? I would think you have about the best gas around. I doubt you have the EPA as we do that mandates all kinds of crap be put into our fuel.