Step side dimensions and gauge thickness

[GMT360]

Hey all,

I'm not having much luck finding any worthwhile fleet or step boxes to go onto the 67 I'm building. That and the axle I've swapped in has left me with a much wider track than the stock axle...

So I've been working around the idea of building a custom bed with stock fenders. I'm not too sure where to look for the outer dimensions of the stock short step bed, I'd like to try and mimic the original style as much as possible, and I'll also admit that I am cheap. I am building this truck from loose parts to stick to my non-existent budget. I have lots of ambition, and endless enthusiasm for making new things...

Thanks for reading,

Jeff.