Here it is. Remember ALL angles are 30 degrees. You'll need to bevel the edges of the top and bottom so they fit properly against the back and each other. The sides are a perfect triangle, again, 30 degree angle on a miter saw. If you're making several, use the stopper, then all you have to do is butt the edge against the stopper, set your miter to 30 degrees, and cut, rotate, cut, rotate. If set right, you won't even have to measure after the first time.
For an 8" lamp I make a 7" hole. Make sure it's centered and there's enough room on the sides to account for: 1/2" each side for the extra inch of the lamp, 1 inch each side so it isn't difficult to remove, 3/4 inch after that to allow for mounting to to the side pieces. Use 2 1" drywall screws on the bottom so the lamp doesn't slide down. When you install the screws ensure they allow the light to sit evenly over the open hole.
Cover the opening with a strong wire mesh. I use 1/2" square wire for my snakes.
The pole on top is a piece of dowel. I put them on top to give my snake something to keep him from falling off when he climbs. Drill a hole down the center except for about an inch. Install with 1 3/4" screw.
Sand smooth, paint, install. The wall the light is mounted to must be open behind the light for replacing bulbs but more importantly to release heat so it doesn't catch fire.
