Sorry,
I'm kind of clueless about that - seems like a few adjustments to make with the long-sleeve shirt to remove the annoying round lump arising from conforming to the M3 shoulders.

I think that is the long-sleeve T-shirt from Ryuten's main freebie downloads:
http://www001.upp.so-net.ne.jp/ruten-ryojo/poser/download.html

Eternal Hobbyist