I've used 3M tape in past and it was solid, i mean, i could push the "window" with my 2 thumbs and it wasn't moving away and the side panel was bending...
You could do some hinge with a magnetic lock on the front to keep it closes and loook nice or do a 90 curve shape at the end and drill holes for the stock screws and attach the front with a grooved panel at the bottom and/or at the front...