Done a lot of searching and can't seem to find what I need.
Looking for ANY measurement you care to pull a tape on from your stepside or flareside or flairside or whatever you call your box. Bought a really nice 72 F-350 with a 9' flareside box (was supposed to be a 75) complete with factory paint on the wood floor and gonna take box off and cut it to 79 short flare specs. After pulling a tape on this one it's pretty obvious all the extra length isn't all up front. I do not have a box to measure so looking for some help with that please. If I'm right the box is taller, longer in the front and longer in the rear.

 

The box sides I think are not the same from 73- 79 . The long box is a rare box also for that year. 1973 has 45 degree angel to the top and the 79 is at a 90 degree angel.

 

Ya it's not going to be an exact copy but when it's done I'd like it to basically fit an actual 79 short and have things like the wheels fit in the fenders and not hang over the back end and stuff. It's going on a project truck for a while so basically anything goes with it but I'd like the box set up to fit a normal truck in the end.

Box has the 45 degree top flare yes. Also has 4 stake pockets per side. Even finding a picture that's similar is harder than it sounds. It also has inner fenders inside the box. And appears to have 5"? Hanging under the tailgate that a lot don't have. Also has a couple mounting holes for the tailgate hinge.

Things like length of box
Front of box to front of fender
Rear of box to rear of fender
These are big things I need. Other stuff is more of a curiosity and just handy to have. Had a few ford guys look at this truck and they all get the stumped look on their face at some point.

 

Will this help. From the Ford Body Builders guide for '76

 

That should just about do it yup. Thank you.
Got a link to where you found that by chance?

Any obvious differences between the 6/8/9' boxes that a guy should know? Little trivia extra credit stuff?

 

FORDification.net - The '73-'79 Ford Pickup Resource