I found a FS2002 repaint for the 727 at Flightsim.com:

http://www.flightsim.com/zview.php?cm=list&fid=57443

The bitmaps probably have alpha channels, which the FSX version doesn't use.  What I recommend you do is download a utility called "DXTBMP" available here:

http://www.btinternet.com/~mnwright/programs/dxtbmp.htm

Then you can open each bmp and re-save it as a .dds DXT1 file.

You don't need the ACE to install the texture; you can just take the texture.cfg text file from another variant of the aircraft, and make a new entry for the variation in the aircraft.cfg.  Just make sure you number the [fltsim.x] the next number in line, and give the variation a unique title.

Good luck!