As far as a generator do they look different than an alternator. The voltage regulator in mine was on the radiator support not the firewall so it looks like it has already been done by a PO. The alternator I put on had the post and the DA plug. The big wire off of the DA plug went straight to the post. I have no clue what it came off of, probably some derby car years ago. Anyway it just bolted in so I figured it would work. It moves the volt meter in the cab when I give it the RPMs.
The key switch was hanging under the dash when I got it, only a couple wires connected. One was for the starter, one was on the post marked ign. and a couple on the post marked acc. I don't think it was the factory key switch. I replaced all the wires on another aftermarket switch but just ran a hot wire straight for the ign. post to the + on the coil so it is getting the full 14.5 volts from the alt. I basically need to figure out where the ballast resistor is then I could know where to stat wiring it up.