[Tom Wesenberg]

In your first picture The center main bolt heads are turned from the factory position. Each bolt head has a tiny bump sticking up to indicate the alignment for the cotter pin at the other end of the bolt. The bumps should either face straight in or straight out so the cotter hole is perpendicular to the crankshaft. As long as the cotters are installed, it's not a big deal, but I'd guess most Model A engine builders would know this.