Like others I can only comment on Rover PG1 proposals.
If the G/B is currently hydraulic clutch its easier to make the changes.
Let me explain, from the beginning the normal Rover 200 clutch is cable the hydraulics tend to come on the 400 and above.
The clutch actuating arm in the bell housing that engages with the thrust bearing is different between the cable and the hydraulic gearboxes. The arm change is simplicity in its self, if you have the arm to change.
The clutch slave cylinder is mounted to the gearbox casing if you have the slave and the bracket no problem if you are converting, you need to get the pair to match the bolt-on position and the stroke of the cylinder and the movement of the arm. The MGF bracket for example provides the rubber engine mount at the g/b end, the slave mounting and the flexible pipe bracket and the pipe as to the body-work if you get all of it together, now you are cooking.
I used the Rover donor steel pipe from front to back so it screws direct into the clutch master. As an aside because it is ridged it can be bracketed to run high in the tunnel front to back getting it out of the way of the other pipes in the floor of the tunnel.
The master cylinder and pedal are a compromise because the 200 donor box is cable and of no use, the 400, that JD and I used if I recall correctly, is a separate pedal so you have to crop off the cable pedal and mount the 400 pedal onto the front bulkhead panel that is made of 1mm aluminium and will need strengthening. All sounds good but it fouls the heater in a major way so you have to move the heater to the near side and get creative with the heater mod to further reduce its width, I managed to cut and shut the heater with a further 25-30mm removed to avoid protruding into the wheel well of the near side panel. The mounting brackets are then in the wrong place by the way.
So now you have the master cylinder fitted, the clutch master cylinder fluid reservoir now needs mounting, I should have mentioned that any master cylinder with an attached reservoir will not fit under the window screen so you have to have a remote reservoir. I ended up with a special bracket to keep it as close as possible and still on the same level as the master cylinder or you have real problems avoiding the window screen wiper mechanicals and bleeding the bleeding system….. Even with the reservoir lid at the same level as the master cylinder I had to get creative to get it to prime the system and I could not easily get it any higher. Once primed and working it should be no problem.
Super; so now you have a working system, well nearly, you will find that the 400 pedal is now way high in the drivers foot well to allow the master cylinder stroke, to give you the slave stroke, to disengage the clutch.
You may need to grind off and re-weld the foot plate in a different position on the pedal link or just bend the leaver. Bending the leaver is a huge task by the way and not for the faint hearted without a 10 foot scaffold pole to hand and a bench vice mounted on a 10 ton rock bed! And an elephant to provide the force required.
As the advert states.. ‘ for every good idea there must be a dumb idea to balance it up’.
Have you heard the joke about the builder lifting bricks up on to scaffolding with a simple pulley, he gets to the top and it hit’s the scaffolding and the bottom falls out of the barrel and the bricks tumble out and fall on his head, so he lets go of the rope and the barrel falls down onto his head and so on… get the picture.
So you end up with a good idea to change to a hydraulic clutch and spend 3 week solid changing all sorts of things to make it happen, they in turn change other things of less difficulty to solve and eventually its all working………
But you have an hydraulic clutch!