You are on the right track.
Get the corrugated PVC started with a a small screwdriver. After you have it started peeling grab the end that is now loose with pliers. Some times needle nose works best on small diameter fittings. Pry with screwdriver and pull peal with pliers.
Sand with 220. Clean, Prime and Glue with the Hot Blue Pool adhesive. Let stand one day before use.
Fill tub and call the Bikini Chicks and make Frozen Drinks.
or it leaks.
Here's to hoping it dont end up that you, fill hot tub only to find out the jet body to tub seal is hard and leaks and it was all for nothing.
Then it is chip-grind the insulation, cut the nut off and new jet and jet body with fresh seal of course.
Please post pictures of the hottest in the tub.