The front suspension is different on the 3.5. The hubs are different in diameter where the shocks go. might be wrong but the lower spec 3.5 didt have the anti roll bar. I would change the whole front suspension.
With regards to the wiring I would keep the wiring the same apart from the engine loom which will be different.
Craig
Last edited by fiesta23; 08-05-2014 at 02:27 PM.