Thanks Rojie for your kind and informative comments.
Since learned that the seat is a 'Welcab' - from the ones viewed in the last 20 minutes or so, most seem to be fitted to the middle of the vehicle.
Going to speak with the guys that look after our stairlift & scooters to see if it's something they are able to manage or, know of someone who can.
I do have a good mechanic but, he is retiring at the end of this year so need to source an alternative before parting with any cash.
Also need to shift the Merc Estate we have at present as it won't be worth much as a trade-in.
Plenty to be working on but absolutely no rush
Thanks again
Kevin