***Post Weekend Update***
Hello everyone, I made some good progress this weekend and if I had not run out of welding gas and materials I could have made a lot more.
I was able to get most of the remaining welding done on the main cage of the frame and got one of the side decks tacked together. I can now get a good idea of how wide this thing is going to be.
I designed the side deck so they would have a nested spot for rocket boxes to be stored for easy access. In this area I am going to put the aluminum sheet under the 1.5" pipe so the ammo cans will sit down two inches. In that recess I am going to add an angle frame so that that the cans can sit snug and have an individual spot to tie-down each can. .
I am starting to think about what type of aluminum sheet to use for the floor of the cargo area and the side decks. I like some of the ideas that other Buzzards posted in this thread. I want to add a lot of tie down points in the cargo area. I like the idea of drilling a "peg board" layout of holes for drainage and additional tie-off's but don't want to spend the time to drill them all. I thinking about using some perforated aluminum sheet in some areas for weight saving and drainage but not sure yet.
Also start working on the cargo hatch design I think I am going to make some frames out of 2" angle and use either expanded or perforated aluminum sheets. That seems like it would give good traction be light weight, and would clean and drain well. I am also going to design these so I can use them as a ramp for access on and off the boat when on shore.
Here are some progress pictures below.