A lot of the locomotives that the Parsons Vale purchased from ILW have enough extra horsepower in them that it would be wasted on any non-high speed traffic, so the TdM shops remade a handful of old first-generation units into slugs to provide additional wheels for the new locomotives to use.
So when the first two of the LT&L’s old RS-1s were retired (#302 & 307), they were pulled into the shops to be rebuilt as slugs.
457 & 458 ended up being the only units to be rebuilt as slugs; 458 had the cab & short hood replaced with an RS-32-style cab and low short hood, while 457 was first rebuilt as a “loaf of bread on a sled”, but later had the cab replaced to make it into a control slug like 458.
457 is now operating in the midwest and 458 has been moved to central Ontario to operate on the lines north of the great lakes.