There is a plate on the bottom that can be removed. It's got four screws. You can remove the two small screws, loosen the big ones and slide the plate off. This will give you access to the bottom. You can wipe the WD40 off any are it may be dripping with paper towels. Most likely that bottom plate will be soaked. If the machine is clean and working I wouldn't do much more than wipe up the WD40. If you let it air out in a ventilated area the smell will likely leave in a day. If it does need cleaning I'd use mineral spirits on a small painters brush and only use it on metal, not painted areas or rubber. Tends to be safer than paint or lacquer thinner, which is more corrosive and toxic.