radio button size

["Boncek, John" <jboncek Hunter COM>]

I'm creating a set of radio buttons using gtk_radio_button_new, etc.,
without labels attached to the buttons.  How do you control the size of a
radio button?  (I need smaller buttons.)  I've tried
gtk_widget_set_size_request, but that seems to control the area in which
the button displays, with the button itself being truncated without
changing size.

This is in GTK 2.2.4, with IceWM window manager.