what should i clean out my trx 15 with? denatured alcohol? wd 40?

Yes, both work very good. I use wd-40 and spray the entire car after I remove the tires and cover the airfilter with a plastic bag. Then I blow it off with high pressure compressed air and then I use denatured alchol in a spray bottle and again blow with air. All of my electronics are sealed completely so unless yours are dont use this method. I race off road 1/8 scale and my car gets very dirty and have been cleaning this way for years with no problems, I do dissasemble the suspension and clean everything thoroughly every two race weekends for a smooth ride.