I hate that I'm asking this but... do I bother going Mr. Clean crazy on the bottling bucket? I'd be fine just spraying it down thoroughly and spraying into the spigot... instead of a gallon-ish soak of Star San.
Put a little StarSan in the bucket, hold a lid on top, and shake it so the inside surfaces get coated. As long as it’s wet for 30 seconds the sanitizer should work. No need to waste gallons of it.