Thanks muchly for taking the time to help troubleshoot. I ran through the same steps as you but I still don't see the HSI change. Here are my mimics of what you did:
Set up the flight plan at KISP
Start flying with input selector to GPS-1 and flight director set to auto and climbing
On track
Now here is the problem. Reached CCC and the autopilot is correctly turning towards KWV but notice the HSI still stays on 86 and the input GPS-1 shows COURSE-86
A look at the navigator looks correct however