Amalfi Coast from Salerno to Sorrento

That amount of time and plan screams to me "private driver"....many people (and many people probably on this forum) have hired a driver for 6-8 hours to see the coast, and it is good because you can stop where you want, go slow when you want, and not be at the mercy of someone else's schedule.....

if you have enough time all depends on what you are hoping to do.....where were you going to have lunch (many of the restaurants in Salerno aren't open too much before 12:30 or 1pm)? Did you want to pay your driver to wait for you during lunchtime? I would suggest maybe eating lunch at Pizzeria la Tombola or Trianon around 1 and then having the driver pick you up from there......there's Vietri, Cetara, Maiori, Minori, Amalfi, Ravello, and Positano to see (plus more that I can't remember, but I think that would be a lot for me!)......I would make a priority list of what you want to see first, and then if you find a company (people can suggest them) ask them to help you see all that you want to see/do.....

Note that many chauffeurs are not "guides" but have enough knowledge of the area to show you the high points. But then you need enough initiative to say, "No, we don't want to go to the pottery shop, but can we use their toilets?", for example. (As we did ... .) This might be 260 Euros for 8 hours. I would start at 8 or 9 AM, to have a leisurely dinner in Sorrento, and see as much of this traffic-clogged coast as possible.

We used our Sorrento hotel's car service partner, but there are dozens of companies in this business. The AC coast is hard enough to reach spedily that rich and poor alike need car services to make their planes and trains back in Civilization. You need someone to be responsible for your luggage during lunch. BTW, you didn't mention the word ... Pompeii ...

Both good points. If I were you, I'd get off the train at Salerno Centrale at 12:30, and it's probably a 10 minute walk to Pizzeria Trianon. It says online they open at 11:00 AM. Have a couple nice pizzas (the Margherita for 5 Euro has been my favorite in Italy to date), relax, and like Katherine says make advance plans for a well-rated driver to pick you up near Trianon around 1:30-2:00 to take you to Sorrento.

Here's the thing. If you want to take the scenic south coast (and I'm assuming you're doing all this in high season, May through September) and see all the little towns, stopping at a couple, with traffic it could take you a good 3 hours, maybe more. Mind-boggling scenery, picture-postcard stuff. However, if you wanted the fastest route to just get there, one takes the northern route and it can take a little over an hour direct to Sorrento. But...that route passes right through...Pompeii.

If you think you're up for it, (and maybe the driver's also a guide?) you could spend the late afternoon hours touring the ruins. Depending on your interest in that type of thing, I think 2 hours is minimum, and you will have only seen half of it. We spent four hours in 60 degree weather in March and were tired, saw about 75% of it but in hindsight wish we could've gone back. There's that much and it's that spectacular, so you might want to devote most of a day to it. Or...do 2-3 hours at Pompeii, arriving at Sorrento early evening, and then take a separate day to view Pompeii's bookend, the Archeological Museum in Naples.

Nice choices to have--enjoy your planning!