I'm entering this discussion rather late, but the two locomotives in the first photo, #1900 and #1901 are both SD24's (According to Lines South 4Q 2005). Although, I have seen SD24's, and they don't look like these units...I'm wondering if my source magazine is wrong? Paducah's famous GP10's and GP8's look a lot different from these.
The Georgia Southwestern was spun off by RailAmerica to a local businessman. When RailAmerica left, they look most of their good locomotives with them, the GSWR had to use leasers for quite some time before they could afford their own units. The different divisions that now make up the GSWR have had it rough in the past, but the Georgia Southwestern is doing quite well now... They have a mighty fancy paint job that mimics the old Central of Georgia scheme..
Additionally, the GSWR did have two Paducah GP10's, #8377 and #8375. They've also got a GP8 that RailAmerica gave them...