Need advice on colour coding wheel arches and bumpers

[yellowcard]

Im looking at colour coding my wheel arches and front and back bumpers and need some advice.
a couple of people say that if i spray the existing arches and bumpers it will come up really tacky.
how does everyone else go about it?

[LoudCorsaGSi]

when i bought my car, the rear arch was broken n parts missin so i nicked parts of my other car n jus sprayed ova them, after a while the paint will chip off, i dint undercoat mine therefore u saw the original colour, dnt help i only put 1/2 coats on, but i would sand them sand to smooth, undercoat them, then spray them in the colour of ur choice

[pipz]

spraying your bumpers will be fine mate, if you doit properly they will be no different to buying new ones and spraying them.
just take you time and they will come out well. the hardest and most important thing is the prep, get that right and they will look cool.
i think theres some guides on here if your worried.

[seadoobabe]

Just make sure that the surface is smooth and clear of any dirk, chips flakey paint before you start and you'll be fine!

[stu_g]

good prep work is the key

[Wonderboy]

Yea prep is the key. When I done mine I used too low grade of sandpaper and it scratched the plastic but they still look... ok... I'm wanting new ones though