I've been running around Europe for the last 10 years in Alfas and never carried any spares.
Bought my first GTV TB in Milan, ran her around until some a-hole wrecked her in Luton. Ran the twinny GTV for 4 years commuting from Frankfurt to Brussels, Liege, Geneva & Scunthorpe (someone has to!). The 156 never missed a beat and I have done over 20k in the GT in the last year - Berlin and back just this weekend.
I had some problems with the steering rack on the 3.0 GTV, it had to be replaced but you can't carry enough spares to cover that.
Make sure your car is correctly serviced, looked after and all the good things are done, brakes, tyres, belts etc. Bear in mind you need to carry first aid kits, triangles etc depending on which countries you are in or travelling through. If you are making the trip before April then be aware of winter tyre regulations.
Don't know where you are going in Italy but if you want to play a little, try Calais, Brussels, Aachen, Cologne, Frankfurt (lots of unrestricted Autobahn
) Basel, Geneva then head for the Mont Blanc tunnel, Torino, Milan etc
There are a lot of roadworks between Rimini & Ancona. I drove from Rome across to Ancona last winter, a great drive.
For piece of mind make sure you have good European breakdown cover, remember that in places like France, Belgium & Italy, english is not widely spoken.
The GTV V6 is made for the autobahn especially as a lot of the posers in their dick extension BMW's Audi's Merc's etc are restricted to 155mph - the GTV isn't
If you need somewhere to stay near Frankfurt on the way down, let me know.