you need just the regulators, switches and wiring, thats it. start at the switches, follow thew wiring. it will run to both window motors, plus there will be a bit to the fusebox. if its a proper vag loom, there will be a fuse and relay.
once removed you should have a live feed, ign live and an earth thats it. only thing is if car also has elec tric mirrors and/or central locking/speakers the wiring for this will be bundled in with the electric window loom, but you should be able to sort this out easily enough.