Nismo,
You can run 18x10s or 19x10s front and rear on the 34. This is part of what Mario had to say on the subject in a previous thread:
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"ATTESA requires that all the wheels and tyres are identical. The same grip level and rolling diameter.
One of the common mistakes that people make is using different tyres (grip levels) and different sizes (your fronts and rears should be the same size, width and height) as any small changes will drastically affect how ATTESA interprets its input.
Tyre choice is also important. If you use crap tyres, don't be surprised to see the 4WD system doing strange things. You bought a performance car, so go out and use performance tyres."
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The fuse/rwd idea is from what I can gather is at best a myth and at worst a quick way to fry your clutch packs. Even it was possible, why would you want to lose the benefits of Attessa for the sake of an extra inch at the rear?
Peter.