The differences in Hendrix' tone from playing upside down don't have anything to do with the headstock or nut (his nut would have been reversed, otherwise his low E string would not have fit in the slot, and the high E string would have been buzzing and moving around in the huge low E slot). It mainly had to do with the reversed bridge pickup, which on a strat is angled closer to the bridge on the treble side (so backwards the way Hendrix played them). And of course all the other gear and gadgets he had.
I always thought the Jimi just played a regular strat left handed; in other words, upside down ? I think the Big Muff paired with the wa-wa had alot to do with it, but, since I was never a big fan, did'nt pay that much attention .
