The actions, scopes, stocks, and barrels all have consecutive serial numbers. The actions I bought as a set, but the other stuff just kinda worked out that way.
There is a stencil set, but there is also alot of "freehand" taping involved also to get the desired pattern with it. I use the stencils for a base, then I start to tape off the rest. I think it is bulldog arms that I get them from. Duracoat also sells a stencil kit, but bulldog is way less $$$.