I found that a good hair dryer was better than a heat gun for bending. I started at the bow and centered the first piece and worked it around with a hair dryer. There were only three places I needed my wife's help, on the bow and both sides of the stern. Makes sure you clean it really well and fill all the old holes. It helps to have two cordless drills, one with a drill bit for creating the holes through the rub rail and into the boat and one for driving the screws as you go. Caulk as you make your way back.
Clean all the old gunk off and sand
All the gunk removed and sanded
Filling all the old holes.
I did a lot of sanding, primer, and painting but once it was time to put on the new rub rail I ordered from D&R I started at the bow.
Kept working my way back with the 20 foot sections.
When I got to the stern I brought both sides around until they over lapped and cut them in place with some cardboard under to protect against the saw binding and scratching the boat.
Then I ran the rubber insert back.
I did not take a picture but I brought both sides of the rubber insert around the back and used the marine sealant to join them.
The hardest part was getting started and believing I would not screw up my boat. It was not a tough job, but I took it slow trying to think my way around any mistakes I would make.
Good luck, you will be happy once you get started.