I have a '97 A4 and I had to replace the entire engine...

The engine that I put in has 46k miles approx. according to the guy I got it from. The odometer still reads 115k which is what the original engine had. Can this be reset? My father is the one who did the swap, he is a licensed mechanic tho not a Audi Mechanic. I thought I could have an answer for him before he came home... any thought?