Now that's what I call rust!
 

Searched around a bit and haven't had much luck seeing how others have tackled extensive rust in the area around the battery tray. (Minor rust, yes, but this instance is pretty extreme)

The car, a '77 280Z, belongs to a friend of mine, and I was initially just sort of "contracted" to wire up a MegaSquirt and sort out the hideously scrambled stock wiring. (All taken care of at this point.) When I got to sorting out the climate control and wiper motor issues, things took a turn for the worse when I started finding more holes than metal on the passenger side of the car.

Now, we knew it needed floor board work, but as it turns out, the firewall from the battery tray down to the seam where the floor pan attaches is just gone. So, too, is the rear of the passenger wheel well, and the front portion of the outer rocker that is covered by the fender.

I'm no stranger to welding in sheet metal, but so much of this is gone that I feel a good cut from a solid donor car may be required. What do you folks think?

Welcome to ZDriver!

To comfort you, I and many others have seen much worse. I traded a set of subwoofers for a 280zx that I literally kicked out the entire floorboards from the seat to the top of the firewall. I used most of the car for parts.

Locating another 280Z that is in BETTER shape and available to chop up is going to be a challenge. If you find that BETTER condition chassis, might as well just start with it. :D Otherwise I'd say it would be easier to fab up your own panels.

You can do it! A donor car will cost you more time and $
I knew nothing about fab work but I managed to do this with the costs of some tools.

First off, thanks for the input and warm welcome. Just wanted to get that out there before I forget.

TheRamz, that looks fantastic! I know my first attempts at patching panels years ago didn't come out that clean looking. I'm better at it now, but my shop currently lacks a welder capable of working tacking together the super thin metal this Z is made of. It's just about the polar opposite of my Mercedes that is so thick, it can have panels patched in with innershield.

I had been thinking that getting a cut from one of the yards in the Southwest might be the way to go, but now that I have picked enough loose bits of rust out, I can see that the parts missing didn't have any ribbing pressed in to them, so simple sheet steel should be acceptable. I was afraid of ending up with oil-canning originally, but that shouldn't be an issue. I just need to upgrade my welding setup and get to work. Miller is offering a rebate on several of their models through the end of the month, including the Millermatic 140 Autoset, and I believe that is what I will pick up. I already have an ancient Miller Thunderbolt 225 buzz-box for thick stuff, but there's nothing on a Z to weld with that monster.

In all honesty, this should have been a parts car to begin with, but I don't think the owner wants to hear that, so I'll spare him. We're far enough in to this thing that we may as well see it through to the end.

By any chance does anyone sell a new battery box bracket? I could probably weld this one back together, but just slapping in a fresh one would be easier, no to mention it would help me align the replacement sheet metal for the fender well a bit better.

My battery bracket was pretty bad too. I cut it out first and got it cleaned up and welded it back in. It's easy to fab up a new tray to replace it unless you want it more exact. You can drill out the spot welds on a donor car but they all seem to be trash.
The replacement panels I made were actually a series of patches that I over lapped so they were stitched welded on both sides to keep from blowing holes through it. Notice the angle support piece. I folded a strip and used a shrinker to curve it. A plastic teardrop mallet and shot bag was used to get the curves and crown of the peices.
Since then I fixed a problem with my welder to get better welds. I treated the area with POR-15 before paint.

Yeah, with the quote I just received on a good used battery support, I would be happy having to weld this one back together. the top two mounting areas are pretty decent, as is most of the tray portion. it is the portion that drops down beneath the tray towards the engine and affixes to the fender well that is rusted away to nothing. I can repair it.

I'll keep my eyes open at the Pick n Pulls, too. the spot welds are easy enough to drill out.