Looking rather impressive old chap! Use the decals, just take your time, and position them using Micro Sol or similar. Probably best to do those running in one direction first, then let them set before doing the others. If you get an overlap, try using a new blade in your scalpel, and cutting the decal in position, where it joins. Any small gap etc can be touched-in later, when set. Gloss paint is better for this, which can be clear coated as required later.