The 03-05 FX45 also had all auto. I checked and it is not an easy retrofit on the first gens. All the switches use different wire harnesses and plugs. Booo!Another thing worth a try is seeing if the window switches in the FX50 fits the FX35 without any wiring differences. FX50 has windows auto up/down on all 4 windows, while FX35 only has auto on the front windows. I had all auto on my previous car so it's a sad thing to see the FX35 without it.