Most clear isn't going to stick for long to the glossy monokote surface. Most planes will do fine if you go over all the seams with an iron set for sticking not shrinking. Most ARF's need to be reshrunk anyway when you get them so it's not exactly an extra step you have to do. A little sealer in places where a seam is facing the airflow (such as trim) is a good idea. Nail polish can be put on and then mostly wiped off and will still be there in the seam where you need it to be.