Wow the pics did'nt load before I posted the above reply, allthough the water putty is still ur best bet and will be the easiest to use BUT if u would have used a LATEX based caulk instead of regular silicone u probably would'nt have such a mess. Man u really need to clean all that slicone up! I would'nt paint over all that mess, it will look like crapola! Why did'nt u wipe off the excess glue? Ok well at this point u need to clean out the port from all that silicone, u should have paintd it black before putting it together,the port I mean. After u clean up the port I would get some 2 1/2" drywall screws & put them about every four to five inches, u need to pre-drill with a small drill bit first so that u can counter sink the screws, then mix up the water putty and spread it EVENLY over the joints all over the outside of the box, then sand after it has had time to set up & harden, not untill then!! After u have done all this then u should have a box that is ready to cover. Good luck, if I can help u n any way just shoot me a PM. Later.