We have a 2005 Itasca Horizon. We just replaced the same part as everyone else because our awning would not retract. We did not have to remove the awning from the coach - there is a much easier way:
With the awning fully open:
We removed the front plastic cap from the awning box. The front cap just snaps on - no screws like on the back cap. (No need to remove the back cap at all)
After the front cap is removed, you will see a white end piece. The end piece is held on by two Phillip screws and a very tiny rivet on the bottom. We drilled through the tiny rivet to remove it.
When the white cap is removed, the awning roller and fabric are now floating free - held in place only by the fact that the awning material is held in the track of the extended aluminum face bar (the one that is extended out and has the "Oasis" label on it.)
Remove the forward end bracket of that face bar (a 1/2" socket) and you simply slide the awning material out of the track.
At this point, the awning material and roller bar are completely free from the coach. The arms, face bar and box remain safely attached to the coach.
We removed the damaged gear from the end of the roller tube, popped the new one in and reversed the process to put the awning back on the coach.
Because we drilled out that tiny (and I do mean "tiny") rivet, we replaced it with a tiny screw.
Took us about 20 mins total.
Best part is: we didn't disturb the original seal/installation on the coach. The awning was riveted to our coach with massive rivets. We didn't want to drill out those rivets because we didn't have suitable replacements.
Mark in Charlotte, NC
2005 Itasca Horizon 40AD