I would consider the disassemble of a seat to be a simple operation. Except in some early cars there are no special tools required. On early seats the covers are anchored with hogrings. These take a special pair of pliers for reassembly.
The seats are held in with 4 screws. Move the seat forward and backward and locate all four. Its easier to do either the front or the rear first. I can't remember, but it has to do with the ability to move against the springs to get to the other two. In other words you have to do two bolts then move the seat to expose the other two.
Take the seat back off the seat bottom at the hinges. The covers are folded into a grove and maybe tied with hogrings. It is very possible that in getting old covers off you will tear the covers they will be delicate. The pleating in the covers will likely need resewing. I would have available an upholsterer for any contingency.
Bosch Master, ASE Master, L1
33 years MB technician