Regular utility knife works just fine. Best to have one that is slightly dulled so it doesn't catch the carbon very easily. I'll usually run it through some tough cardboard a few dozen times to take that burr and edge down just a bit. I assume these arrows are machine fletched. That does make things a lot easier too. Start on the back of the vane, peel a corner off the base and just rip them off. Then use the knife to just scrape lightly. Once you do a few it's really easy. Some of those machine fletched arrows you can just peal the old fletching off by hand without the knife.
Clean the shaft with a high quality lacquer thinner. Let dry for a half hour (at least) before fletching. Avoid getting lacquer thinner on your nocks. Seems to dry out the Polycarb rather quickly leaving them brittle. Unless my nocks are really super tight I remove them before I clean with thinner.
If you are re-fletching with a cyanoacrylate glue I have found wiping the shaft down a second time with a disposable blue shop towel and distilled water seems to give me the best bond. Just be sure it is completely dry before fletching.