It's tricky to get at, the battery and tray has to come out, you'll see the MAF bolted to the side of the airbox, the lower bolt is tough to get at, it's close to the radiator, one of those
snake/flexible extension thingies makes life easier.
Having said that, the engine management light coming on is not necessaily the MAF, it can come on for all sorts of reasons. You really need to connect to the ECU and read the code. You could take it to a garage to be read, for which you will be mugged, you could see if an AO member in your area will offer, or you could do it yourself with a laptop, the trial version of
FiatECUScan and a suitable K-Line cable.
All the best
Pub