pull the tank off pop the #2s out and pop in the new ones, smear a little fluid on them before pushing the tank back in, use the bmw spec fluid, not sure if you have the same standards down there, dot 4 is the recomended fluid here, dot 3 is the most common avalable and it usually eats those grommits, i am figuring it's the alcohol that does it. they generally don't need bleeding