I've been using Simple Green for years. Spray it on as heavily as you like. Lifts the majority of stuff right off and only some really heavy stuff may require some scrubbing. I'm a professional detailer and use it on car engines and everything. Knock on wood I've never had any type of electrical problem of any sort. Also, can't tell any performance difference between normal and automotive Simple Green. Used both extensively. I even use it daily as a tire cleaner.