grub theme displays minimum 3 items if 3 or more operating systems are installed

[systema]

Hello,I would like to change the minimum to 1 item (display one operating 
system) but still retain ability to scroll through remaining OS. I have not 
found a duplicate of this question online or in any documentation. I have 
searched /etc/grub.d and /etc/default/grub with no success. I have used a 
scroll bar in theme and reduced menu height to that of the item height & 
text height, but grub still displays a minimum of three menu entries. This is 
referenced at http://wiki.rosalab.ru/en/index.php/Grub2_theme_tutorial ; quote 
"Also note, that minimal number of shown items (N) - is 3." I have also tried 
wrapping '+ boot' with a '+ hbov/vbox', but this steals focus from boot menu. I 
also tried setting the 'item_spacing' to a negative number which sent grub into 
an infinite restart loop, which required a live boot to correct it. Any feed 
back on whether this can be achieved or not would be great. Thanks in advance 
from Tema.Sorry for duplicate - not sure first email was sent as web page time 
out.