Running graphical install inside existing Guix System

[Ben Sturmfels]

Hi Folks,

I have an existing Guix System running on my laptop and would like to 
install Guix System onto a brand new larger hard drive, connected by a 
USB-to-SATA cable.

Could it be possible to run the graphical installer from within my 
existing Guix System to partition and install onto the new drive rather 
than messing around with a bootable USB and rebooting?

I realise there's lower-level tools like "guix system init" you could 
use if you were happy to partition and format the new drive manually, 
but it would be such a great user experience to leverage the existing 
graphical installer from withing Guix System.

Regards,
Ben