Yep rcs liquid mask is the nuts, i spray mine on through the airbrush & flash dry it with a hairdryer after each coat, usually go for 4-5 coats & after the final coat i always leave overnight in the airing cupboard so it can go off properly
Check out Jon's site for paint choices, rcs is now called rc identity, used most of his stuff & it's all good, his chrome is in my opinion the best in the business by a country mile
http://www.rcidentity.com/
I tend to get a 3l bottle of coke or similar & cut it from top to bottom down the middle, then wash, rinse & use it to test spray things onto