Hello fellow Datsun Nutjobs

Late last year picked up a 1972, 1200 ute with an a14 swap. (Pictures Later)

didn't look too bad for a car of its age and i was told it had some work done to where the floor pans were replaced and so were the sills aswell and it had an approved pinkslip ... so i was like sweet should be fine and its not going to snap in half when I'm driving so i can go straight into improving brakes, suspension wheels and all that jazz... But i got it home stripped the entire interior where i found a stack of cancer and a welding job more dodgy then a bloke standing in a dark city ally by himself...or a car salesman at a dealership

so basically the cowl or "plenum" been clogged for many years so water has been trapped in there, causing the cowl to rust out, in turn rusting out the side guard supports, firewall, kick panels, sills, as well as rusting though the cowl and allowing mother nature to dump water all over the floor, making the floor rust out... but the previous "repairs" were so poorly conducted that the floor and footwells has rusted out again (probably wost then before) and has caused the chassis rails to start rusting out aswell.

But living as a full time 3rd year apprentice mechanic I struggle to have the funding to send it off to the old panel beaters so I have no option but to do all the work myself

so basically I plan to cut the the whole floor out at once treat and reinforce the chassis rails from the top and then obtain floorpans and the side guard supports from automotive panel craft in Sydney weld it all back in.
I have spent come hours searching for some solid advice or procedure of doing this but I have made no progress

so I was interested to know if anyone has already achieved what I plan on doing and if there is any tips or sources they could share with me or anyone else really.
I was also curious to know if I should brace the chassis before I start hacking away at the floor seeing they don't really connect to any other main structure of the car just to stop it from caving in hahaha.

I very much appreciate anyone reading this and will very much appreciate anyone with solid and descriptive advice
Thanks For Reading :)

(i will post pictures of any progress for others)

Easy As. Take a few quick measurements before you start to make sure everything is square. Brace any part you are going to cut out. (Zap a few bits of 75mm angle iron in)

Have a look here for measurement to aim for:

http://datsun1200.com/modules/mediawiki/index.php?title=Measurements#Body_Alignment

Water Box Rust

Classic