Just replaced a the element on my NEFF U1721 after the previous one blew big style taking the fuse with it.
Since then I have noticed that the oven seems to get very hot – the temperature light does not go out even after oven has been on for an hour.
Fitting is an oven out job. From memory you’ll need to get the facia off to access a couple of screws for the switch end, then you’re chasing the capillary down into the oven box. Fiddly, not difficult.