1979 1 Ton frame?

[Patriot]

Hello fellas, I'm new to the site but not new to turning wrenches. I have a question for you 73-87 wizards. I just bought one of my dream trucks and it served as a tow truck in its past life. It is a 1 Ton Dualy 4X4. I need to know if there is a difference in the 3/4 ton frames. The frame has been cut(torched) and all kinds of crap welded to the frame. I use to run a weld/machine shop and graduated from an Autobody class and had my own Autobody business for a while before getting called out for this war so working on or restoring a truck is second nature to me. I just can't seem to find any info(frame dimensions) on these trucks on the internet or in my books.

Thanks fellas in advance.

Patriot