I've installed a number of alarms and I never soldered all those wires. I'd crimp them (w/ butt connectors) since they arn't voltage sensitive (in most cases) unless your just a neat freak.

Oh yeah, check that link I posted up top for wire colors, some of them are year specific, and the ones listed on the vfaq are in general.

Joel Baldridge, ASE Certified Master Technician, Audi Certified Expert Technician