Best cleaner that I know is "Bar's Bugs" about $4 for a pint of concentrate. We don't use alcohol much down here, as the temperatures aren't that bad (-7to-11C in winter).
Have tried 1/2c Ammonia, some metho (denatured ethanol), and 2L water, for not bad results, but not good this winter.
Household ammonia is pretty mild stuff, when there's 40T of anhydrous at work.