I have a 4.10 D60 I can open up and pull the ring and pinion. actual mileage is unknown. truck is a '86 bullnose with the 5 digit odo. I have a project in need of 3.55 D60 gears. let's talkI need this.... i have 3:55's and am ditching them.. How many miles were on the truck that you took it out of ?