The more we dug, the more we discovered... Left quarter was really bad, trunk floor completely rusted and had big holes covered with silicone, right quarter was bad, tail light panel was almost gone... Right inner fender was poorly repaired at some time (later I discovered that the car had a small accident and got hit in the right front fender at some point of its life).
So we reached this moment where I had to decide whether to stop and clean it up all we can, repair it so that it looks nice from the outside, but I would have this understanding and knowledge that the car have cancer underneath the shiny paint... Or I could do it right. Expensive, time consuming, but right.
Aaaand yes, as you have already figured it out, I chose pain, tears and empty wallet.
We took the engine out and prepared to tow the car to sand blasting.