Making a simple offline USB installer
 

Hi, I work on a SBC based system currently using QNX. I have decided to move to an open Linux platform. After much fishing about I've settled on Arch. It looks to be well maintained and has all the functionality we require.
What I would really like to do is to make a USB that boots into Arch (already got that working) then to run a script to partition the SBC DOM (hard disk equivalent) and install the Arch system boot up WITHOUT using pacman - the users will not be online.
I don't need a GUI, the TTY is fine for this application.
Thanks in anticipation of a great solution!

Have you considered some pre-made image where one could use a tool such as dd or other to send it over to the internal drive?

Thanks Jefro, I was looking at dd and it is likely to be part of the solution. What I'm currently thinking is that I'd like to set up the Arch system with all the scripts, directories and our applications installed, I can easily do that, and from that create an ISO which I could thenceforth use for the installation. I'm looking at ReLinux just now but I'm finding the documentation a bit scant - anyone know if that would do what I want and, if so, how?