Yeah, it's hollow. It prints upright, as though aiming at the ceiling directly overhead. Takes from 5 to 7 hours to print, depending on how fine the print.

Considering what you had to work with, you did an awesome job. It's a pretty rough kit, with virtually no detail. If I ever get time I'd like to add the little wheels and levers, but for right now it's a "20 footer". Looks fantastic from 20 feet away and that was kind of the point. A quick cheap accessory that will look good on any battlefield. I like your idea of an IR field piece. Now where could we hide a servo to give it a bit of traverse?