NYNH&H O716 was the very last DL109 of the New Haven’s once impressively large fleet; it outlived the New Haven’s others by being converted to a third rail power test unit, and then by being tucked away in the NH’s Boston yards.
Unfortunately the New Haven was absorbed by the Penn Central in the dark days of the late 1960s, and the PC had no interest in the trashed old Alcos that were cluttering up their yards.
Fortunately for O716 staff at the TdM shops did have an interest in this particular trashed old Alco, and could pay good money for it plus get it off the property ASAP. So it was transferred to TdM ownership, towed to the nearest SLR interchange, put onto a pair of freight trucks, (s-l-o-w-l-y) shipped up to Iberville for a pretty serious rebuild (including a pair of 251D-6s and modern electrical components) and then put into service on the LT&L as a freight unit.
This is what it looked like when it was towed up to the TdM shops:
And this is what it looks like now: