Save trouble, give me the car!
Beautiful car. I think you should give your car to me rather than fixing the seat.
If your car is low mileage it might be hard to find a replacement seat that is better than the one you have, and matching the passenger seat would be unlikely, right?
Have you thought about getting the seat refurbished instead? You can probably get the existing fabric or leather professionally renewed or replaced for less hassle and cost than getting a new seat. There are chain and Mom/Pop places that do that sort of thing. Get both fronts done at the same time.
I don't know specifics about 740 seats, but car seats in general are not mechanically difficult to remove. They're way heavier and much more awkward than you'd think though, so get a friend to help with the actual lifting or you'll blow your back out.
The seat frame bolts to the floor pan in most cars (again, 740 different?) can get really ugly. If you can get penetrating oil into the bolt holes a week before you want to take the seats out you can avoid disaster.
Actually, that goes for pretty much any job on a car that's old enough to be out of warranty.