My winter project. 1974 W100 Utiline

I'm looking for some info about the truck frames. I would like to have an extended cab, short bed 3/4 ton 4X4. Is the std. cab long bed the same length as the extended cab, short bed? Could I do this, or would it be impossible/too expensive to be done.

j


I am not 100% sure but I think the extended cabs frame mounts were different.
My dad still has his 78 short bed, extended cab that he bought new.
I can post any pictures if needed.