Hi john you best bet is to use plastico the principle is to sand your spoiler with 400 wet and dry, then apply the plastico before priming, check out my website for any further help and also tell a few people about it, we are in lincolnshire -
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hope this helps mate, the best paint that you can get is spies hecker, in my opinion! When you say 2 pack, are you referring to 2k which is a 2 : 1 mixing ratio with hardener? ALSO CHECK A FEW LINKS ON MY WEBSITE, AS I GET PAID! Glad to be of help mate, any questions email me via the website