OK now about the alternator; several things have to work to be able to use these things. Since the alternator is usually on the outside of the assembly most do not have a large center opening that we can say pass the e-shaft through. For a E-shaft concentric alternator we need a HOLE about 40mm (at least) to fit the shaft through regardless of which end of the engine we run the alternator on. We also need to mount the alternator windings to the engines cases safely. This is doubly true of the magnetic rotating assembly. The large center hole is the area I expect the most trouble with.