In 1964, class B #220, plus segments of wreck-damaged Bs 221 & 215, was rebuilt into a (for DC) superpower class B1x locomotive, and after working around the system settled into a career of being a helper locomotive for the Green Mountain subdivision. Alas, in 1992 the talgo joint failed, and when it went into the Portland shops for a careful inspection before repairs the railroad found a whole bunch of cracks in the center trucks, thus converting a fairly routine repair into a rather more expensive rebuild.

Instead of that, the Portland shops did a full remanufacture of the unit, discarding almost everything but the frames and rebuilding it as an almost double class BCC, but with EMD-ASEA electrical systems like the ones in the class Is instead of the old DC ones.

What came out of the shops was the class II prototype; a 3-section (the talgo joint on the B1x incarnation of 220 was considerd suspect, so the two center frame sections were joined together to make a (sort of) class K B unit)articulated locomotive riding on 7 class J trucks: 21000(!) continuous(!!) HP, with approximately 1800(!!!) kN of tractive effort. Fortunately the PV&T had finished power upgrades to the Nashua division (Nashua<->Albany, including the infamous Green Mountain subdivision) so #220 & a class E or I helper (220 can move a long train through Vermont at 60mph, but tends to stringline trains on the curvier sections of the line) move trains without melting the overhead or blowing up a substation.

In 2015, 220 went back to the shops for another round of upgrading; this time the class E plate trucks were removed, sills were welded onto the frames, and it was set on a set of radial trucks (equipped with boxpok wheels).

The STATE OF MAINE paint scheme was inspired by the BAR’s potato cars, but is modified to specify what the product is.