I have looked every where to find low back seats. The 2cv does not have lowered floor pans - not possible as it has a straight ladder chassis - and therefore the seating position is higher. Subsequently the seats will interfere with the head rest on the humps. So the key is to find seat that are very low but still offer some comfort. You do not want to tower out above the windscreen..
In the end I called Intatrim in the UK and asked if they could supply their Apollo model seat with a lower rear height. It cost 20 pound extra I believe but they fitted perfectly when they arrived. The only thing is that the seats are really narrow while I would have had space for a wider model. Its still OK, but if your bottom is a bit wide its not that comfortable. I could either widen the seat or lose some weight (and thats what I did...) Now they sit excellent!
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Also bought the Sabelt seat belts - I did have to have to weld some mounting brackets.
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