My compliments, it takes some vision - or vision problems - to see a "classic" in a police bike. What cop stuff comes off and what new parts go on doubles the choices for mods. You made a good decision in the spokes and whitewalls, since these really go a long way to changing the look of the bike.
The trouble with trying to match whitewalls to birch white is that the whitewalls are too white when new and too brown when they age. For myself, I try to stay with the too new look (scrub with magic eraser). In bright sunshine, I'm the only one who notices the whitewalls are too white.