Well done David.
You are in for an interesting time.
While a 24volt system in general, the ignition is actually 12v, gives more reliable starting, which is pretty evident from your clip.
FYI, the jack ( a surprising extra) fits across the transmission tunnel behind the front seats, along with the starting handle.
I would suggest inspecting the 3 round water jacket plates on the block behind the generator, they can eat out from the inside and let go with no warning.
This crowd in Tulsa:
http://www.khakicorpsimports.com/spares.htm
stock a lot of B series parts, Thermostats is one to take note of as they are quite unusual and hard to get at times. Most of the electrics are the same across the range of vehicles.
Most of the Champ fraternity is very helpful, so when in doubt, ask.
Just to give you something to look forward to:
http://www.youtube.com/watch?v=YH6MtkUTmtI
The screeching sound heard occaisionally as the Champs hit the water is the fan declutching, a neccessary design feature as the fan is mounted on the crankshaft.
Best of British luck to your resto!!
Rich.