In the late 1990's, UP had 10 AC4400CW's on lease from GECX. The units were numbered GECX 4000-4009. The units wore UP colors, but instead of "Union Pacific" on the long hood, they had "GECX". The units were ultimately purchased by UP and put in the roster. They wound up as UP 7000-7009. Here, you can see the number "7" patched on the cab over the "4" on UP 7008.
With the addition of UP 7008, I've managed to shoot four out of the ten ex-GECX units to date.
