I would venture that you will probably use them more than once. Mine are used constantly (and a lot of it trying to answer forum questions somewhat correctly). Without trying to be an a-hole, there's a lot more to it than just a single exploded diagram. The main engine controls consist of maybe 7-8 pages of digrams, and then add in the connector pinout diagrams to that, and even the others for power distribution and grounds. It's not an easy thing to just post up either. Cheers!