You might find it easier to jack the car up on the side you are working on remember to chock the front wheels and use axle stands as you don't want the car coming down on your head.......

The fiat handbook says take the car to a dealer to have this done but if your prepaired to lay down on the ground its not that difficult

the bulbs in question are both (382) P21W

In this guide i'm doing the Fog light for the simple reason i can get the camera in to get some half decent photos (the Reverse light is obstructed by the exhaust back box...

you need to locate the bulb holder.. (the bit the wires go to)

now grasp this firmly and rotate about 1/8th of a turn anti clockwise where it will stop rotating..

(make a mental note of where the bulb holder sits as you need to put it back in this position before it will close once you have changed the bulb)

now pull down. and you will release the bulb in its holder

next push bulb down slightly and turn anti clockwise to remove

to refit reverse the above just remember to get the bulb holder in the correct position when putting it back into the lamp unit..