Hello Darren, welcome to the best teardrop message board around. It looks like you are really dedicated to actually building a teardrop trailer, good for you. Remember, this is the perfect place to ask questions as you go along, and you will always get an answer, if not many. I see you are looking at a HF trailer, which is a trailer that has been used by many, including me. You mentioned the need for welding and I wonder where any welding is going to be needed. Are you planning on metal fabricated support members for the sides and roof framing and then covering with aluminum? I suppose you already know that most of the "aluminum" teardrops are really wooden ones that are clad with the bright, shiny aluminum skin.
I just want to encourage you to start building as soon as you can, do continue your plans for a galleyand by all means take pics as you go along, we just love pics. Good luck on your build, and welcome to the wonderful world of teardrop camping.

Roly, the li'l ol' So Calif TD builder (and user)