Like with any wash, you always do top down, leaving the dirtiest parts for last.
Try using ONR at QD strength of 6-8oz/gal from a hand held (garden) pump sprayer and then a bucket of rinse water with a grout sponge - spray, wipe w/sponge, then dry w/MF towel one panel at a time. Rinse sponge ad needed. (kind of a cross between a wash and QD).
Note: Spray ahead for dirty areas (tires/wheels) for more dwell time.