I'm likely to be refitting my seats this weekend (at long last). I want to replace the nuts bolts and washers whilst I'm there. The old ones are not in awful condition but I might as well, eh?

Question is: should I use BZP or Stainless A2 nuts and bolts? Why?

It doesn't really matter Neil. These fixings are not stressed, so stainless is fine. But if the originals are reasonable, try putting them in vinegar for 24 hours. Clean first with white spirit to remove oil/grease, and they will come up really well. An old restorers trick.

Ok, my seat transformation is done.
In the begin i have provisory adapt the seat that he could be back completely.
Now i have transformed the high of the seat that he moves without problem, in the same winter works,I have renovated the foam and the flex of the seat, he is now like new. The carpet is replaced (DIY handmade from a doormat) and fixed.
Dave thanks again for many ideas, more Adaptations are done or will follow.

A yes, still a question. All the screws are too long, for the technical inspection(security) the need to be cut?

It's OK to cut the ends off underneath, but might be harder to fix next time!!! (unless you use new long ones & cut again).

I don't think the screws under the must be cut to pass the inspection. If so, I would be in trouble with the original setup.

Harald

Yes the old one what to short, as Dave said i had to replace them.
I Think “wait and see”, in April a have to go