ANDY welcome to irv2.
We had some threads on Vintage forum of rebuilds and pictures but files are now to old or missing.
There are links in stickies for parts and some members have their threads on there rebuilds.
I guess its pretty much up to you how you want to go abut your rebuild.
On your good wall take measurements of studding and nails or staples into them to copy for new walls.
Most stock are 2x2's with insulation than re-paneling, have rebuilt slide-in for son replacing some wall rebuild and bottom deck of slide in.
You just need to copy and write down how to progress the project.
Have fun and get your kids involved they will enjoy helping.