The rust shown on the original image is not terrible to repair. A shop that is competent in metal work can make a repair piece and graft it in perfectly so finding a part from a wrecked Ferrari is overkill and will cost more than it is worth. It would be wise to have a few sets of eyes look over the entire car to identify the overall condition before starting anything. Realistically given the age of the vehicle, one way or another you will end up painting the whole car so bear that in mind longer term. Given where you are located there are a ton of shops who can do the work for reasonable money. Not too far back I oversaw the metal work and paint for a friend's Dino by a shop near Huntington Beach. He knew little about the process and asked me to check in on the shop he had chosen. While the work was not destined for a show, I was blown away by what the shop was able to do for the price they charged. Feel free to PM me and I can give you the contact info.
I admire your courage in this endeavor. Don't give up on your path as many do. Come back often for questions and advise, this forum has seen it all and the knowledge here is incredible. Keep posting progress photos as you go along, we will all want to see them and it will also help you document where things go later in the future if you happen to forget. Im definitely following this post! Good luck, but for some reason I don't think you'll need it as your determination is quite heard. Welcome to FChat !!
The good news is the section below the beltline back there is fiberglass. The bad news is that rust will have gotten down into the wheel wells which are steel panels that make up the floor of the trunk/boot area. But all of those panels other than the quarter panel are separate panels that can be unriveted and tack welds cut and simply replaced. I should have saved the patterns I made when I replaced all of mine. The really good news is none of the trunk floor panels require any finish paint so can be done at home pretty easily if you can get the panels fabbed up. I agree with others about getting it mechanically sound and driving it for a bit. It's not going to fall apart any time soon, drive it and enjoy it for a bit. If you want to possibly stop the rust from getting worse dab some POR-15 on there and open up the trunk and paint some around too. It won't stop it because you won't be able to get to all the metal areas but it might help slow it a bit. I documented my rust and metal replacement in this thread about my interior resto... https://www.ferrarichat.com/forum/posts/135928051/ https://www.ferrarichat.com/forum/posts/136539493/ Image Unavailable, Please Login Image Unavailable, Please Login
And I should ad that I had holes about the size of the one you posted but mine were up by the side markers. I had those repaired after I bought the car but they must not have pulled the trunk carpet and seen all the rust in the first pic. Or at leas they sure didn't say anything about it if they did!! I had the holes repaired though and most of the rear quarter painted for about $5k.
