I am wondering how diffucult and how long it will take an experienced mechanic to take the stock gears out and put 3.73s in? I am looking to get these and I am just trying to figure out how big of a job it will be for someone to put them in.

 

Hey look at that, a FAQ with all sorts of helpful info. Heck, #5 even goes through the installation step by step!

https://ls1tech.com/forums/gears-axles/412366-rear-end-faq.html

 

Figure about 2 hours for an experienced mechanic.