It ended up being relatively simple to seperate off the subframe and runners, although a bit of hacking was required
And both Nigel's and Kenno's advice above was very helpful ... thanks gents
Here is the donor seat, which a friend kindly provided (for nowt!)
To get the subframe(s) off, you simply need to undo the two torx bolts at the back of each runner - shown
here .
To get the runners off, you need to remove the seat base cloth and foam. I started by freeing up the
back with a screwdriver/pliers, then
pulling that through to the front and then
working round the base until it was free.
There are then
four nuts to undo, which hold the runners to the base. Strangely, just on one runner, there was also a single
rivet . It wouldn't drill out, as it span, so I hacksawed through it.
The end result ...
subframe and runners .
Now I just need to fabricate an adaptor plate to mount my race seat.