Latest seabios (aka git master, 1.7.3 isn't new enough) can append the seabios log to the coreboot logbuffer. So you can use "cbmem -c" to read the logs once the system is up'n'running and find the strings there.
Then I suggest adding that information to the wiki: http://www.coreboot.org/SeaBIOS#Configuring_boot_order when that feature is in the stable release.
Thank you.