Redirect or change "You do not have sufficient permissions to access this page."

I currently use a plugin to prevent non admin users being able to access /wp-admin.

When an non admin user is logged-in and tries to access /wp-admin it shows the – “You do not have sufficient permissions to access this page”, which is correct.

My issue is that I don’t want it to show that page instead I’d like to redirect the user or show a 404 page – how can I do this?