DANG
8 bit no work
32 bit, everything works except body, then the game crashes after about 30 seconds
I obviously don't know which Cherokee 6 we're talking about so I did a quick search & found this one here.
http://www.simviation.com/fs2004props63.htmIt might not be the same one but on this one the original fuselage texture (cherokee6_fuse.bmp) is in 256 colors (8 bit). You can find out the format by opening it in DXTBmp. You should be able to save out in this format direct from Photoshop after repainting. If not you can save in 24 bit & use the 'Extended 256 colour' option from DXTBmp to convert it. I tried & it works fine for me. I think all the other main textures are in the same format.