Started my W.12 build. Like a few others here, I decided to tackle the floats and their decals first. If I was going to make a hash of the decaling I wanted to know that up front so I could change my build before I began modifying parts. Complicating matters was the fact that I didn't have the correct Tamiya paint (XF-83) on-hand.
After assembling the tops and bottoms of the floats, I sprayed gloss white on the tops.

After letting the gloss white dry for a couple of days, I applied the decals. I cut each decal into three sections and they fit perfectly, going on with no problems except for the expected issue of them not snugging down over the ribbing and other protuberances. Micro-Sol was sure my friend on this--until I went one application too far and some of the needle pricks opened up when they dried.

Once my XF-83 arrives I plan to air brush the undersides and brush paint the white sections on top. To minimize the white showing through the decals my thought is to lightly spray it with Tamiya Smoke or to give it a light mist of a buff color. I'm thinking that the sea water would discolor the lozenge anyway. I'm also trying to noodle out how to apply a splotchiness to the floats (and the sides of the plane) to represent the effect of the salt air and spray on the paint. That's a ways off. Whew.
Thanks for looking!
Mark G