I had my hatchlings in shoe boxes for a bit and they didn't even have clamps but did great. The little buggers never got the lid off (and my Lily tried like the ****ens!). I did have them in a 29 gallon with clips on in case they ever did escape but now have them in a rack (still in shoeboxes). So far so good. You'll probably be fine (though I have heard of people using bungee cords for extra security when they're a bit stronger). Good luck!
BTW - is it a normal? morph?