@blackrat, maybe laser cutting sheet metal is a good plan as I know its going to cost way less than what these enclosures cost but I'm probably going to have a very hard time to arc weld it together. I've tried welding thinner material but it was hit and miss and I burned holes like you wont believe even with 2mm rods, so there's much to learn in that department.

Clive, now that's a great looking box! Those LCD displays really got my imagination going... Can I extend the offer for free beer and sunshine to you :-) I'm a bit scared of butchering an expensive box with what tools I have. I have not done the layout yet as suggested by Eddy but I was guessing maybe 600x400x300 as a ballpark? Content would be 1x PC ATX Powersupply, BOB, VFD(vfd face outside the box) 4 x Drivers and few relays. The driver are quite big at something like 180x160x60 if I recall correctly and I would like some spare space for future expansion.

Excuse my ignorance but what's those white square things in your box?