Q about the Messiah2

[Silence]

Ok, I'm a noob... (just as a warning)

I've been reading the stickies, the newb guides, doing searches on topics, etc in the forum, and I've got a question that hopefully someone can answer.

My PS2 is the USA PS2 NTSC SCPH-30001, and from the version reference charts I've checked out, it seems to be a v1 board.

I recently went to a shop to get my PS2 mod'ed and was told it's not possible. From what I've been reading, this seem a bit strange?
Are there specific models that the Messiah2 DOESN'T work? According to the messiah2.com website, it seems like almost every PS2 version is covered...?

Help... I'm... confused *:/