can't get rid of those highlights
Photoshop, photoshop... but it's hard work, so better source material (lighting wise) makes your life easier.
You could have modeled some parts on the sode with real geometry, now it looks quite flat/photoish when viewed from the FPS viewpoint. There's some (mapping?) problems in the trigger guard area, and some (jpeg?) artifacting shows too, maybe your source material was too small or something.
But generally speaking it's quite ok, and certainly better than most ppl here can model/map.