Looking very tidy. I used a 5mm perspex for the rear (outer) window, again cut to a home-brew cardboard template by the shop. Think about using a tinted glass/perspex window; Why? Lots of tall 4x4 cars have high mounted headlights, that can dazzle you through the rear view mirror, even on dipped beam. A 'tint' will take the edge off.
Keep the updates coming.