Just a quick tip. The Funivia del Monte Faito reopened just a few weeks ago. We found out about it the day before we were leaving Sorrento and it was literally the hightlight of our trip.
This is probably the best cable car ride in Italy. It's amazing. You can get to it via the Circumvensuvia and it's just a few stops from Sorrento, and a longer ride from Naples. The station is Castellammare Di Stabia.
It's incredible. Unmarked really, but right there as you exit the Circumvensuviana. You buy tickets at the train station (make sure you buy a roundtrip ticket. When we went last week there were no lines. It was just us and a couple from Austrailia. I don't really know how it would handle large crowds. There seemed only to be one car going in each direction. It's about a 10 minute ride to the top, and you will have the most spectacular view of Naples, the bay, mountains and surrounding areas.
It must have been at least 20 degrees cooler as well. We got there early. I would advise the same.
Again, it has been closed for a few years for renovations. We are lucky we found it. Google it, you will get a better idea.
There are also some videos posted on youtube before it closed. There might be new stuff posted by now.