To ANSWER the question:
The "head" must always be first when exciting the funeral home. This is TRUE for all Hmong; Green, White, Black, or Red -- at least for SE Asian/Western Hmong. (Who knows regarding our Chinese amigo-Hmong, as they have had 1000+ years of Chinese assimilation.)
As for the burial site and how to position the body (head/feet); that is all dependent on the location or "Looj Mem". The NORM however, despite the location, is that the head rest on the East, and feet towards the West. This is so that as the sun rises, it will raise the head of the deceased, as if waking him/her up, or arising them from their sleep/death. (Yes, this is the general/popular Hmong belief.)