So, I've had a couple of thoughts.

I'm thinking that I need to weld up some sort of cross bracing laterally before I start cutting all this out to ensure the car doesn't flex...more than it has. Is this necessary?

Ideally, I'd like to find a donor car and cut the complete pan out of it and work that. With the limited availability of rust-free parts cars, I've wondered about the viability of using a pan from a W123 chassis car. I know they are different, but I'm not sure whether or not they're SO different that it wouldnt work. Not 100% sold on this yet, but it's an option I'm considering.

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