Goat,
Sorry, I have nothing for a 2SL-1 unit and it's been years since I looked at one. Last Montgomery I looked at was a star wheel traction.

Montgomery used relay USDR to affect a stop to an intermediate floor. If you place a one floor run, does high speed pick up? Look at what controls your slow down when it comes into the floor.

I'll look in my files and see if I can find something useful for you.