You can override the simple command card option for your map with override player option action
Sorry had an old enEU locale first then i uploaded wrong file, should be up now
Here you go. Some instructions in the triggers.
It uses the top row of the units command card rest buttons are hidden away.
Doesn't use layouts at all.
Requires void dependencies.
I don't think its possible to do with the default command panel, seems like its hard coded to hide the buttons when you start targeting. I could try creating modified version of the Lotv Spear of adun command panel
What are you trying to do?