Current Projects chat and miscellany

so here is my current problem. This is the back of the trike box

and these are the bars I want to attach

(they're huge!!!). I'm thinking of cutting them just above the curve at the base of the rise and clamping the bits to the corners of the box. These corners are made of steel and are quite strong. I'm not sure of how to do this. I've got one of these from a dynamo light and it seems to do the trick
http://www.sjscycles.co.uk/busch-and-muller-high-quality-aluminum-stay-fitting-bracket-bmd23-prod11215/
but it's quite pricey. does anyone know of any other bracket that could do a similar job?

this is the current extent of the trike build, nearly there!

thats badass, you've obviously got a lot of new stuff on there and homemade bits, but the old royal mail style tarp just makes it completely awesome looking (and anti-theft'ish).
whats inside the box? I'm hoping for a comfy but battered up old armchair, tv and tea mug holder, also there should be heavily patterned brown 1970's wallpaper on the internal walls. Maybe on the external walls as well, just because.