Isopropyl 99% in an ultra sonic cleaner (jewellery cleaner machine) - take the motherboard out and set it to clean at 80 degrees and then look for corrosion any clean that off with a toothbrush a soft one - please correct me if I'm wrong ifixit because I'm new still for now but ya and leave it in for a while not too sure how long I'm sorry - you will see a bunch of guck and stuff floating from the millions of bubble that get into every single little hole we can't and you should be good to go! Do some research on it and look up what I typed here and you'll be in the right direction ! Hope I helped
--Motivator Luke W on fb if you want to chat but these ifixit guys rock this stuff like you wouldn't believe ! I love you guys and gals if any!