If you don't get a response from the dealership (or agent representing the seller you entered the financial agreement with) in a 'reasonable' amount of time, write back to them stating what you want, in that further to your previous communication dated ***,
1, An independent evaluation has found and stated in writing that the operation of the clutch system was defective and the fault has been identified with the mechanism outside of the excluded wearing parts listed in the vehicle warranty statement and present since the vehicle was built/prior to your ownership.
2, Under terms of the warranty, you expect the defective parts to be repaired or replaced and all other parts damaged as a consequence of the parts failure to be replaced at no further cost to yourself.
3, You allow them a stated time period to respond to the request with an appropriate plan of action (1 week from the date of the email/letter for example)
3a, (optional) You require a courtesy vehicle whilst yours is Off Road. (If you have one of theirs, it can speed up their decision making process)
4, If they fail to acknowledge the defect was present when the vehicle was built within the time stated or they fail to commit to carry out the repair to meet your reasonable expectations, state that you will make arrangement for the repair to be made elsewhere but you will seek to recover through legal means (Small claims court) ANY out of pocket expenses such as the cost of the repair, vehicle recovery services moving the vehicle to another repairer, time spent dealing with this issue at national minimum hourly wage rates, documented phone calls, costs of reasonable alternative transport arrangements made (bus, taxi, hire car, fuel@45p/mile and time of somebody else moving you about).
Make a detailed record of your time and expenses accumilated whilst dealing with this since you presented the vehicle to them on day one of the failure.
The more you detail, the more pressure you put on them to sort it out as they can see your costs are escalating. Don't get angry with them, it doesn't help.
Be prepared to do what you state in writing to them otherwise they will not fulfil your expectations.