To start a big fault with Rover 25/200 series 1996 on (bubble shape) is that the sunroof has a bonded seal and this is not available to buy on its own
The seal is bonded to a metal rim and then the glass the metal rim rusts quickly (4-5 yrs) blows out the rubber seal which in turn allows the water to penetrate (in the winter this is made worse by frost) once this happens eventually it will leak .
Rover dealers will charge £290.00+ for a new sunroof (if they can get them) and fitting is not included or you can use a breakers and pay around £90.00 and most will remove it for you. (most good breakers remove the glass tracking, motor and control unit and sell the item in one lot) If you require a good breakers whom deliver anywhere in the UK and overseas please email me.
To fit the sunroof yourself this will only take 1 hour for a novice or 30mins for a professional I have just done one myself on a Rover 25 and it took me 30mins and I am not a professional
19mm , 10mm , 8mm socket or spanner flat bladed screw driver & cross head screwdriver
1: First if possible break the seal on the sunroof (open it slightly) then remove all the door rubber seals and the tailgate rubber seal.
2: Remove all the plastic trim around the roof lining (this is a good time to get the flash out and give it a quick clean) most of the trim just pulls out (has snap clips) you will also need to remove the seat belt (19mm socket or spanner) if you have passenger assist handles fitted remove them now 4 cross head screws.
3: Using a flat bladed screw driver remove the internal light cover remove the bulb and using the 10mm socket remove the 2 retaining nuts, remove the electric plug.
4: By the top of the drivers and passengers door there is 2 plastic lugs use the screw driver to remove these, there are also 2 larger plastic lugs by the back windscreen remove these as well
5: Remove the headlining through the tailgate
6: The sunroof is now fully exposed locate the drain points (each corner) squeeze the wire clips to remove locate the main power plug this goes to the black controller unit (2 wires) unclip the internal light cable, then remove the 11 retaining nuts and remove all (you may require help to lift the sunroof from the car at this point)
7: Put your new sunroof in and hold in place with 3 nuts one in the front centre and 2 on the rear DO NOT do up tight
8: Put the cable back for the centre light, plug the controller back in, and put the drain hoses back in
9: Now you should be able to open the roof about 6 inches, replace all the nuts but only hand tight now close the sunroof and make sure it is centred if not open it slightly and adjust then tighten all 11 nuts
10: Replace the headlining handles, plastic trim and rubber door seals.
Hope this helps and it may also be the same for 400 and 600 series Rovers