Ok Gear Instalation GuRu's, This is weird. I bout 2 sets of 4.56 gears from National Drivetrain as well as an Eaton Posi for the rear, and both install kits. i am haveing these gears professionaly installed, and even the shop guy has never seen anything like this in like 15 years. My rear went togeather perfectly. However, my front pinnion gear will not set to the riht depth. Usualy, they have to use shims to bring it out slightly to track corectly. However, im my case, with no shims, it is out to far. The guy doing the work says if he installs it that way, when i put it in 4 wheel, it will chew up my gears in the front. He Originally thought it was just that the one pinion was not machined all the way, so he took the gear set out of the rear, and tryed it in the front and it had the same problem, so it is not Gears themselves. He spoke with National Drivetrains Tech, and his solution was to put a Twenty Five Thousandths shim in and force it togeather. He even said that he rarely ever measures when he is building a rear. What kinda technical advice is that. The company is stupid. If i had known that ahead of time, i never would have used them. I would have spent the extra and gone with Randys Ring & Pinion. Has anyone ever come into such a problem before. Please help. My truck has been in the shop for three weeks now. Just to swap gears. Any help is appreciated, and one final note, Never Ever buy anything from National Drivetrain again. Thanks Ike Spreading The K5 Gospel!