I snapped mine a few weeks back too, got my brother to try and change them for me but we had trouble getting the heat shield off to access the cables because of the bolts just spinning and also had little room to attempt to get them out...we ended up giving up so I'm going to get mine done just before my MOT haha...and as mentioned, change both of them, it'll cost you about £70 for the genuine Renault cables (got mine from Wests Renault on here!)