Alfa 147, 156 & GT
The wiring info gleaned from this group and alt.autos.alfa-romeo helped but wasn't quit correct.
My Bella is a Nov 2003 147 1.6TS Lusseo UK spec
( all directions from rear of car looking forward into car)
Reversing light on hatch is served by 2 wires, white/black is power,
purple/black is earth...