My dad restored and painted cars for about 30 years and probably painted and rebuilt more than 50+ cars. If you want to really do a nice spotless job, you have to have a clean dust-free area. DA everything down so it's smooth with a fine grit paper, wipe with wax and grease remover, and base coat of primer. After that, DA some of the primer down, and respray it on again, really thin layer. After that, spray the color you want, let it sit for a day, wetsand, respray again. Then clear it really thin layer at first, wetsand, then lay it on (not too thick) after. Sounds complicated, but I have some pics of a few cars he painted like this, and MAAAAAN are they nice. I also painted a guitar this way, and except for a single fish-eye that showed up on the back (which I scuffed out) it works flawlessly. Provided that you have a clean-room and a good spray gun. Spraypaint looks good to an extent, but when you gotta paint a large body panel or hood, it will be inconsistent and blotchey.
Ummmmmmmm...............Petroleum+Rubber tire=BAD TIRE
If you don't want to take the tire off the rim a little masking tape and newspaper work wonders. I know it takes a little time but you not left with a greasy mess when you are done. Plus your tires won't rot prematurely.
Paul
Yes newspaper and masking tape does work wonders for tapint off trim and whatever. You can also use newspaper to clean windows with - Doesn't streak. Does shred a little though.