Firstly, neither seat locks in place. I think they are standard seats which have been recovered in leather, but there is no locking mechanism, so seats just slide back and forward in the runners.
What do I need to fix this?
Secondly, the accelerator linkage keeps falling apart.

The bottom of part 3 in the pic keeps falling out of part 1. I thought there was a clip missing, and so have some other people I have spoken to, but it would seem it just goes in there and the shape should hold it in.
So either part 1 or 3 is worn, but part 1 seems unavailable and anyone who has part 3 says "not CU"....which of course mine is. Any help/suggestions/CU type accelerator parts for sale welcomed.
Thanks in advance