Hi. Thanks for your interest in doing a Thai translation. I'm sorry but it is not yet supported by LFS.
If we did support it, it would use the Windows codepage as seen on this Microsoft web page :
But at the moment we do not support Hebrew, Arabic, Vietnam or Thai. In the case of Hebrew and Arabic there is an additional complication, that the writing needs to go from right to left. It looks like Thai does not have this complication so I would just need to implement the Thai codepage and characters into LFS to make it work.
I like to support languages and I find it interesting, but I can't do it until the highest priority things are done. At the moment that is the new tyre physics, VW Scirocco and Rockingham that everyone is waiting for. Maybe you could remind me again after those things are done?