Quoting Steve Ward
hey! this is awesome! ive just bought the sub, i wondered if you had any instructions to add to the length of the original model? i particularly like the space for sleeping/storage space for the divers suits!!
Its pretty simple. Just add some more plates to the bottom and reinforce it. Then do the same with the walls as the front part by taking off the bubbles from the top. It thats not enough, I can take a few pics of it torn up a bit.