When it comes to cleaning your trim tabs, Matthew Anzardo from Interlux recommends cleaning the metal with a solvent like Special Thinner 216. As acetone dries very quickly, sand with a 60-grit since some trim tabs are super hard to sand. The 60-grit gives a good bite into the metal. Blow off any residue from sanding so as not to get any cloth fibers sticking on the metal burrs. Apply about four coats of InterProtect 2000E and then apply a compatible antifouling. It is not recommended to use copper based products on aluminum. Copper based antifoulings can be used on stainless steel with the proper amount of primer applied.