regarding the Elmira branch, the north-south (former PRR) part of the OMID is mostly 130 PS. And as Gordon says, it is not the same section as other similar weight rail.
I have an old track chart of the Elmira branch it's not complete and only shows Horseheads north to Newark. It does show three short sections
of 152lb rail.
mp2-4 listed as 52-51c probably still there 152lb installed 1951 just north of HO.
mp10-13 52-50f
mp42 52-53c
don't know what the c or f means
A little oddity the miles are listed in feet as 5332,5299,5302 etc.
Charles