if you are using internal cups for both top and bottom do you need the headset reducer?
For flexibility, it may be better to put an external 1 1/2″ cup in the bottom and then use the headset reducer as if you subsequently change to a tapered fork you won’t need to buy another lower cup and bearing.
Just a thought
Edit:
don’t use internal bottom cup!!
From Cotic website:
Our new frames have adopted the external bottom cup regardless of whether you’re using a 1 1/8″ steerer or taper. Whilst a regular zero stack bottom cup will fit if you’re using 1 1/8″ forks, it steepens all the angles by 0.5deg and more importantly for frame longevity, you will have no fork adjuster clearance to the down tube so using zero stack bottom cups has strong potential for damaged forks and frame as well as slightly shady handling
