Dug out some old track charts:
The spur at the south end of Montvale Yard at Cross Street was refered to as the Hill Yard (not to be confused with Ayer's Hill Yard). Looks like there was one grade crossing - Holton Street.
The Grief Brothers siding was off the Swanton Street siding right on the northside of the undergrade bridge.
The siding off the northbound track at Cross Street I referenced as Parker & Lane was once shown as General Gelatin.
In answer to the Woburn Loop signal question - Yes. The power switch and associated signal were nevr retired and remain part of Winchester Interlocking.
I also found a Telegraph Bulletin Order from 3/21/75 taking the Stoneham
Branch from Maple Street (Lindenwood) to end of track out of service!
And last but not least, there was a list on customers in Iron Horse Park:
McQuesten Lumber, Johns Manville, Fortek, Penn Culvert, NH Shippers, Food Center Warehouse, Purity Supreme, Chemical Corporation, Wood Fabricators, JA Webster, Torngren Co., Northeast Cement, Grossman, Whittemore Perlite and Northeastern Ammonia Co.
Dave