Having now interviewed as an external and internal candidate I can say that these are not the same interview process, which I understand, but these were drastically different for the role of equivalent pay grade.
As an external:
1 phone interview with HR 30 minutes
1 interview with management (3 pay grades above role) 1 hour
1 presentation to senior management (5 pay grades above role) with Q+A followed by interview with team seniors (2 pay grades above role) 90 minutes
For internal:
1 interview with team seniors. 1 hour.