For those following this thread, here's where I've got to:
After trying a multiplicity of different approaches to remove the Tetroseal, so I can see the state of the floor, this is what I settled on:
1. Apply white spirit liberally, with a paint brush
2. Let it dwell. Long enough to work but no so long that it flashes off. About 15-20 mins during winter weather seems right
3. Wipe off. Use rags if possible as they are more absorbent. Otherwise, the Scott blue towel paper
4. Repeat steps 1-3 above, as required.
It's boring so I break it up. An hour here - an hour there. Oh, and I always open the garage doors for fresh air, and wear a respirator with vapour resistant filters.
Here's the current state of the floor:
2024-01-13_12-28-53.jpg
Yes, it still has some Tetroseal but most of its gone and I can see what's what. I'll remove residue bit by bit.
The areas of concern to me are around the rear of the wheel arches. Here's the left side:
2024-01-13_12-30-19.jpg
I removed the fuel tank stand so that I could get in here and clean, then examine the area. There are at least two patches, which don't appear fully welded. Some 'holey' metal. And a section on the wheel arch that seems it should be connected to the boot floor, but isn't. Not sure what to do here.
Here's the right side:
2024-01-13_12-32-06.jpg
That beige coloured stuff is filler. It has gaps in the fold that let light through. It's close to what I think is the connection to the sub-frame so I'm concerned about the structural strength though research tells me there are three folds of metal here?
What all this has shown me is that I should invest in a welder and a training course! So, that's next on my list

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