Dude as far as I know you have to buy a new one. because it wasnt sealed right in the factory. Even if you can fix it it's going to be a crap load of work. Sorry
Some of my friends at the German MX-3 Community had the same problem.
They fixed it by smearing some silicone round the seam. I've never heared that anyone of them had this problem again later.
I got some of those lights also. They are all the same (LEAKING). All you need to do is dry them out indoors then seal them up with silicon. At the top of the lights in about the middle there is a small slit, this is were the water is getting in.
good luck trying to get the clear lens to come off cleanly... I ended up throwing mine out and now Im left with one 'tezza.. Oh well, Im doing the Supra tail-light conversion soon anyways.
I think I'm just gonna try to dry it out by using a blow dryer or something...I dunno...! If I succeed I'll let you guys know how I did it. As for the Supra taillight conversion....I don't really like it! I'll start a thread for that issue though!
Are these the altezzas that were sold on ebay??? I saw the prices a couple months ago from 140$ a pair down to 90$ a pair....I was wondering why they were so cheap. I had my suspected that moisture might be able to penetrate through them bcoz of some leak. ugh...