I dont think that you're gonna get a permit for your neons.
Just like you wont get a permit for your subwoofah or your pedals/paint/gearknob because they do not affect the impact crashworthiness or mechanical function/capacity of the car.
Like Dan said, if you cop a sticker for your neons, go to welshpool and plead your case to Reno.
Provided that everything else on the vehicle is legal, they will tear up the work permit for you. However, if you do not have the good fortune of everthing on your car being 100% legal, then you can hardly complain that the policemen was misinformed, and that it wasnt your neons, but your welded diff that he should have stickered you for.
So my advice is, if you want people to look at your car, then expect attention in all its wonderful forms.
and if you've got a bomb held together with gaffa and zip ties, dont make it glow like a freakin xmas tree.