So I made the lexan cover today. I used 3mm cause that's what the local plastic place had. It took me all day to do this and I still couldn't cut straight. Even though I got a fairly tight fit it makes the battery huge. I might have gearing issues. I did originally make it 5 sided but it wouldn't fit so I cut part of the back off as you can see bellow. It's also now too tall for the top stopper so I'm going to have to use a velcro strap but the one that came with the kit is too short.
Here are the pics: