An even easier and possibly cheaper alternative: I used Nyalic. Simply sand the ally bright, then apply with a cloth. Admittedly it's only been 2 years, but so far it is still perfect.
Nyalic, the worlds most advanced nylonic clear coat solution for marine, architectural and industrial corrosion protection
A $200 can is enough to do 3 rigs my size (16m by 235mm and double spreaders)