Dude, we said this before, the M7 EMU HAS, been made. It sounded like the old R143 by Eddie Yee,, but with a slower propulsion. It WAS on TTMG.org along with the R142, R29, R160A/B, until people started modifying Trevor Logan's trains which he didn't appreciate so he took all his trains down from the internet. So you're kinda behind dude.
If I were you, i would try and contact Trevor and ask for the M7 though the answer will most likely no. If i could help you, i would.
Back on topic... can't wait to finally see some LIRR action! and is there any possible way that you could send me that route you just ran? I wanna use it as a test track