The new seat arrived today, this is virtually the same as the previous seat but does not come with the mechanical suspension unit. This seat only has the fore/aft adjust and recline. I took the head rest and arm rests from the old seat and fitted them without too much trouble, but for some reason this seat does not come with the lap belt fixing point, so I had to remove the back rest and drill a couple of holes. It's back together now with lap belt installed. With the new seat support and battery compartment underneath I had to get rid of the suspension unit, hence this new chair, which means a weight saving of at least 12Kg.
Also spent some time getting webots running on my Dell Linux machine ready for code development. Webots doesn't run that well on this machine, the frame rate is pretty slow but usable. However, it crashes out when resetting the simulation, which is a pain in the arse, so will need to spend some time looking into the reason.