The instrumentation works, and you're doing it in the same key as the Animals did it...with enough twists in the instrumentation to make it your own.

You'll definitely want to recut the vocals, (given some of the wavering) ...maybe even try a key change to see if you can belt it out more????) and yeah, hold that money note for as long as you can, and end on it alone.

And you might want to check out these versions as well the one Ben suggested...especially the second one. You might find a real original slant

frijid pink version
http://www.youtube.com/watch?v=t40INnb6DnY
(they start on Em, G, A, C, Em, G, B vs The Animals Am, C, D, F, Am, C, E)

tommy emmanuel version
http://www.youtube.com/watch?v=WIWSVTaytOw&feature=related
(watch how he plays it...quite complex actually)

If writing ever becomes work I think I'm going to have to stop