When confronted with some unexpected rust in my new (to me) 240 turbo I darn near freaked, after all I'm in California!!   Rust is something you folks in the snow belt deal with, not those of us in the sunbelt.  It turns out there is a plug in the firewall that was missing and every time it rained water poured in, soaking the carpets on the drivers side eventually causing the rust seen below.  Thanks to the folks on Swedishbricks I heard about Por 15, the best invention ever.  The car is now very solid and with the leaks (yes multiple) in the firewall fixed I anticipate no more problems.  This is a very labor intensive and messy process so I didn't get as many pics as I would have liked however the instructions with the Por 15 Trunk resto' kit are very detailed, and I really can't add anything.
This was what I was faced with once I scraped all the loose stuff out of the way, the Por 15 instructions said it would cover holes but I wasn't sure about the strength so I fabricated some reinforcements out of stainless to cover the large hole #1 and the front of the foot area that was almost totally loose from the rest of the frame #2.  The rest of the holes I just covered with double layers of the fabric and several additional coats of each of the supplied paints.
The Metal Ready that is provided in the kit is great stuff, it turns the rust back into something close to the original metal.   You can see the top of the front reinforcement #1.  I bent it so it conformed to the step on the seat base and went through the opening and supported the foot area from the bottom.
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Here you can see the process almost complete, the reinforcements are in place, #1 & #2 and the layers of the provided mesh and silver "paint"  have been applied and the floor is getting solid.  I put the quotes around the "paint" because this stuff is harder than any paint I've ever seen.  If you ignore the advice to "wear the gloves" you will be wearing the paint until the skin flakes off.  Three coats of the "chassis coat" and the floor was solid as new.  The underside of the car presented issues dealt with in the next page.

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