Correct me if I'm wrong, but isn't the FPA on a longer frame than the standard FA like the FP7/FP7?
If not, the Grand Canyon Railway painted the FPA4s in two different paint schemes. One was CN inspired dark green and the other was the current silver and gold paint scheme.
Caught these in 2017 outside of Williams, AZ awaiting the development of a railway museum in N. AZ that may or may not happen.