how different would the uprights of an AU2 Xr8 be to the ones found on eseries falcons? there is a cheap set on ebay along with hubs and calipers and i was wondering if its even remotly possible to modify and fit them?

They are quite different, but I am looking at doing the same thing myself.

Have you thought of using the AU upper "A" arm?

Then the only problem is the lower end, that is where I am concentrating my thoughts. The lower end is quite different between the E and AU series, have a look underneath an Au if you get the chance. BIG differences!!

i was thinking of getting a custom upright machined, one that would bolt up to eseries, but accept the AU hub, rotor and caliper (helluva expensive)

im probably gonna get em, and an eseries upright to compare and decide what to do from there