You can easily set the body height in an article layout during creating of the article shapes.
Enable Prompt also for Body Size preference
1.On the Edit menu of the Pages main tab in Fred4, select Preferences.
2.On the Extra tab, select the Split sub-tab.
3.Tick Prompt also for Body size.
Create a article shape
1.Press H and then draw a marquee on the page.
2.When you release the mouse, the dialog box appears:
3.Enter the headline height (with or without measurement unit).
4.Select the number of decks.
5.Enter the body length in lines.
6.The shape appears on the page, having the headline and body height that corresponds what you entered in the dialog.
When you resplit this article layout, or replace it with another, the heights will be kept.
See also
Create headline and body columns at once
Create side headline and body columns at once
Create headline, body columns and image box at once
Create headline, body columns and image box at once (v2.1)
Set the headline size when creating an article layout
Create headline and body columns with specific type size
Automate headline scaling in an article layout