The other thing I did was add in the railing for the bed. Like the sheetmetal, this angle was salvaged from work. I was tasked with demolishing some steel shelving last year and I was originally going to throw it in the s**** bin until a realised it would come in handy for something. The natural perforations were perfect for plug welding to the sides. The rails actually sit one inch lower that where the floor will sit because the floor will be supported by a 1x1 RHS rectangular floor.
Great work mate! Love seeing the process, you've inspired me to give it a go making my tub. Luckily I'm going for a shonky looking street roadster bed and don't have to make it as detailed.