posi and gears

i want to get a posi in my 02 blazer and aslo want to go from the 3.42 to 3.73 i was told i might need a new carrier and bearings. what would i have to get to do the job from start bto finish and will 3.73 fit in my original carrier. thanks

a new carrier no. new bearings would not be a bad idea as the pinion bearings are sometimes hard to remove

not sure if you know, but if you change the rear to 3:73 you need to change the front to 3:73 as well.