The Steelton Mack aerialscope is actually x-Harrisburg, the 1971 rig was sold to Steelton in rough shape in 1990, it was rebuilt by SFD members over several years.The story of this Mack is in Dave Houseal's 1st book, "We can see it from the bridge". Steelton does have an xFDNY engine.
This is how it looked in the late winter of 1992.
WW Jenkins photo
This is how it looked in the late winter of 1992.
WW Jenkins photo