Can NetBSD on USB stick force root to be identified as sd0a?

["Thomas Mueller" <mueller6724%bellsouth.net@localhost>]

Is there any way to force a USB installation to identify the root as sd0a, when 
the disk number would normally be variable?

I could put in kernel config

config netbsd root on sd0a type ffs

but would NetBSD still decide for itself and fail to boot if it decides some 
other device is sd0?

Or would NetBSD actually recognize boot device as sd0?

Other possibility is to go to BIOS/UEFI and set boot priority with the NetBSD 
USB installation first.  I haven't tested that yet.

This question is mainly for NetBSD 6.x as opposed to -current, where I could 
use NAME= with GPT partitioning.

I am practically abandoning NetBSD 5.x, not updating any more, doing very 
little on 6.x , but have a 6.x USB-stick installation that I might want to 
update, both i386 and amd64.


Tom