yea u will have to cut the old fiat connector off the old indicators.
but first, u will need to get the arch liners off, may have to jack the car up an take the wheel out for that as well, then u have to push the old indicator out from the back, then cut the wires off, crimp the new indicator wires onto the old ones, remember to check if the indiactor works at this point, if everythin is fine push the new indicator wire through the hole and try to secure them behind the arch liner to stop them moving around. if they are universal and use that sticky black stuff at attach them to the body work i would recomend using some sort of sealer (silicone is best) all around the hole on the inside of the body work to stop dirt an water gettin into the indicators.
after all that is done an u are happy, stick arch liner back on, stick wheel back on if u had to take it off (makes it 100 times easier to get liner out if u do!) and there u go, fancy indicators, only took me a couple of hours when i did it!