i did this on my 2dr
u need
2 FAT width rolls of masking tape
4 or so copies of the local advertiser / newspaper
a scotch brite pad (like a brillo without the soap)
fine grade wet and dry
paint of your own choosing
etch primer if u want to be flash
stanley blade
thinners
towl
The last 3 are only if it goes wrong, you can first inhale the thinners, by smothering yourself with it on the towl, and then slash your wrists with the stanley (meant as a joke, no offence intended)
ok, tape as close as poss around both edges of the trim, then paper allong the tape and tack it on, as if u were to do some panel spraying
use the fine grit, without water to scuff the chrome, u dont need to remove it, just Ԛ´keyԚ´ the surface with fine grooves to give the paint a surface to adhere to
then take the thinners and using the scotch pad, scrub the trim clean of dust from rubbing down, the repeat with the thinners on the cloth
surface is clean, but dont touch it
Etch primer if u have it, works great on metals
Then if u want to be really xtra u can rub the surface down again with wet fine W/D paper(1200 or finer)
then dry surface (only if u did the last step)
And then bit the bullet and spray the fucker

really light coats, or u will get drips and pitting (when the paint bubbles from the propellant)
about 6 coats will sort it and as long as u have maked it well there will be no dripping onto the body or windows