I've just performed this little stunt on a W plate 1.6L 16V Scenic Alize and it was nowhere as easy as you would think...
The sensor (made by renault) has two quite deep captive nuts fastened to the front plate that will only fit into the rear of the mounting points on my vehicle (not the front) as shown in your pictures. This means that width of the sensor now causes serious clearance issues and it took me 20 minutes to get the old one out and nearly an hour and a half to get the replacement in.
Because you have to come at it from the back getting the sensor back in requires you to work blind in a space not quite big enought to tilt the sensor to its correct orientation without serious risk of damaging the wiring connector (I seriously recommend you don't try to fit it with the wires pre-connected).
The whole process is seriously hampered by the placement of the main wiring loom only centimeters above where the sensor should go (as in your pictures). This loom is unmoveable and caused me some serious grief- as it seems to be deliberately designed to hurt anybody attempting the process via some quite sharp dodgy moldings on its underside directly above where the senor fits.
All in all a pain. I'm not a mechanic, but i am reasonably competent at this sort of stuff - and I wouldn't attempt it again on this particular type of car - my poor twisted fingers will happily pay for someone else to do it next time.
This car has only got 33k on it and this is the second replacement that its had.
A poor product badly designed.