I think you Corsair looks great! I see what you mean about the decals silvering though. It still happens to the best of us. On my last couple of builds, I had a couple of areas that I just wasn't 100% sure if the surface was going to be smooth enough to avoid the silvering. As a precaution, I put a SMALL drop of Future on the spot where I was going to apply the decal. When I placed the decal, it caused the small drop of future to spread out under the decal. As a result, I didn't have any silvering whatsoever. I don't do that to every decal I place, only on the ones that might be questionable. So far, I've had good luck with it.
After all the decals have been placed, you can then apply your favorite clear topcoat to seal the whole works.
Eric