Editing the Pace Training Data Screen on Forerunner 255 Music

Hello fellow Garmin users,

I need some help editing the data pages on my Forerunner 255 Music.
I’d like to change the bottom data field on the pace-training specific first data page (see 1st picture).

I can’t change it through the normal Activity → Data Screens menu, since I only see the pages I’ve created myself.

What I’d like to do is have the heart rate scale (as shown in the 2nd picture, at the bottom of the page) displayed together with the pace training screen (the one showing the red–green–red pace zone bar).

Is there any way to either edit that page or create a custom one that includes the pace training display and the HR scale? I couldn’t find that specific pace display among the normal data fields.

Thanks in advance! Stay fit!