The drawings for the jigs are on the Mastiff drawings. I am not sure which one you are meaning.
The cam lobes were machined using an eccentric jig with the required angles marked on the edge - same as I have used on various twin eccentric engines like my Stuart 5A. You mount the blank cam on the mounted eccentric with a line pointing at the first angle marker, machine it, the rotate the blank so the line points at the other and machine it.
The assembly jig is nothing more than a clamp to hold the cam shaft vertically, two bars and a plate with the required angles on it. As you slide each cam into place you point it at the required angle and let the loctite set.
Jo