This is ex Union Pacific UP #8079 built 07/1979, renumbered to UP #3588, sold to Southwestern Railroad as SWRR #3588. EMD Serial No. 786218-15

a typical for the time set of four CF7-slug pairs power an eastbound local to one of the potash facilities located on the Carlsbad Industrial District about ten miles out of Carlsbad, NM

I'm not much for roster shots, but a GP-35 with ALCO trade-in trucks, in the middle of New Mexico, now that's just too cool.