Reg,
saw your post in Chris IH R190 build thread and did a quick search for the sound of the V12, seems to be plenty of files available. The last link is an actual KW truck. Hope this helps give the truck more life, just wish I was from The Land of the Giants, really would be cool to drive your model around. Terrific informative build.
http://www.rigsofrods.com/threads/38...el-12V71-sound
http://ets.modhoster.com/mods/12v71-...-ludmillapower
http://www.musicbiatch.com/download/...roit-12v71.mp3
cheers
Paul