Sleeping Naked?

I'm guessing I got your attention with the title eh? Well someone in our family thinks sleeping in the nude is the best thing in the world. The only problem is that this someone isn't potty trained! Yup you guessed it, Kaiden. Every time I put him down for a nap he ends up naked. Let me just give you some background on Kaiden's nap time. He use to go right to sleep when it was nap time but we're not so lucky anymore. For a while he started playing with his toys and you could always tell what he was doing b/c he was so loud. Since it would take him forever to fall asleep we started putting most of his toys in the closet (we have a child proof door knob so he can't get in). This really seemed to help. He would occasionally kick the wall for a little while but then would fall asleep rather quickly. But now he's gotten where he doesn't really like to take his naps. He's tired and rubbing his eyes so I put him in his room and close the door (that's right he can't open this door either!) and then its very quiet for at least 30 minutes. For awhile he had me fooled that he was asleep but every now and again I would hear a little bang and he was moving his little chair onto his bed. We told him the chair needed to stay on the floor and not his bed but when he continued to move it we finally took it out of his room. So now he's found something else to do while bored in his room besides sleeping...undress himself and chew his books up. He's torn pages in his books before so he only has those cordboard books on his shelf but now he just sucks and chews on the pages then spits them in a pile on the floor all while hanging out in his birthday suite! We've now taken ALL of his books out of his room but I'm not sure what to do about his need to undress himself. He's taken his clothes off a few times before, when he had his cast on but he stopped after the second time we fussed at him. But now its much more serious. After every nap time he ends up naked! Yesterday I thought he was asleep but then I heard him talking to himself so I went in his room and there he was sitting in the buff, and he'd wet his blanket too. We got everything cleaned up and clothes put back on. He got a spankin' and we toke away his favorite toys for the rest of the night. I stress each day that if he takes his clothes off he won't be able to play with his cars or watch any TV but it hasn't seemed to help b/c he's still undressing. Today I really didn't think he would do it b/c after talking to him about it he seemed to fall asleep pretty quickly. I went to check on him later b/c he'd been sleeping a long time and there he was curled up with his blanket with nothing on! Once he woke up Joe put on his diaper and had him watch as he put all of his favorite toys on top of the TV where he couldn't reach them. Kaiden would really get sad that he couldn't play with them and understands its b/c he took his clothes off. I think we're going to keep his toys tomorrow until after his nap to see if he keeps his clothes on and then he can get them back, hopefully this will work. I'd be fine if he just wanted to take his clothes off but its the diaper that I have the problem with. We've been lucky a few times when he hasn't wet the bed but there are those times when I have to go and wash his sheets yet again. When is nap time a thing of the past? I know he doesn't want to take a nap but he's so grumpy if he doesn't. And WHEN and IF he does fall asleep he usually sleeps for a good two hours at least! So how can he take a two hour nap one day and then not blink an eye the next? Does anyone have suggestions on how we can convince him to keep his clothes on?