This is not my advice, but comes directly from another member on another forum on which I participate. Perhaps his advice will help:
"This is from the "for what it's worth" department... My son replaced my starter a couple of years ago and while it was difficult to get to the bolt that runs through the transmission bell housing it was not impossible to do. It took two extensions and a universal joint in between them and a bit of patience. I can't imagine the frame changed much from an 88 Spur but it may have. It looks impossible, but it is possible. At first he, too, thought we'd have to disconnect part of the exhaust system but we did not. He did all of the work in our driveway with the car on jack stands. The bolt that passes through the bell housing is the only one that gave any trouble at all. Again, take that for what it's worth since my car is a 20k series Spur from 1988."