I'm assuming you're looking at a Canada truck.
On US trucks and cars, the MPH is around the outside of the dial, with KPH in blue around the inside of the dial. I'm assuming the Canadian truck are similar, but with the position of the numbers reversed (KPH outside/MPH inside), so all you'd have to do is look at the alternate set of numbers for speed.
The odometer is a different story. If it's calibrated to display KM, you'd have to get it reprogrammed to display miles. I'm not sure that's possible. But you can convert from KM to Miles by multiplying the reading by 0.621, which would get you close. In other words, a display of say 50,000 km would be 31,050 miles.
Or you could swap out the instrument cluster for a US cluster. It could be used - would have to match fuel type and your wheel odometer display - 02 MY and later trucks have electronic odo display, which isn't compatibly with your 01. It's a pretty simple swap. Your odometer would be different than the actual km/miles on the truck, which IMO wouldn't be a big deal. Maybe more important to you. I'm not sure a dealer can reset the odo either direction. That would be a question for your local dealer to answer.
Hope that helps