The taller tires will affect your feederhouse angle and the angle of the machine. We changed to bigger tires and put a mud hog on a 1460 years ago, and I remember having to adjust this stuff. The feederhouse angle can be changed by loosening the 3 or 4 bolts on each side that attach the feederhouse to the throat of the combine, then adjusting the long allthread to tilt it back some. You'll probably want to do this with the header on so you can see the angle of your cutterbar to the ground. The rear axle block has 4 different positions it can be in. If you have an owners manual, there is a chart that will tell you what position you need to have it in based on the size of the front and rear tires. Hope this helps!