I would add this to every ones already good advice. I have installed lots of gears in Chevys, and TWICE in my lifetime I found going from 3.73s to a faster gear, one was 2.73 & another was 2.56 the pinion was physically too large to fit into the rear axle housing. Only saw this happen twice. On one truck we got another axle housing & gears dropped right in. On the other the chosen ratio was ditched for another.
In hindsight I think it had to do with the year of the housing. It was prolly one that was made before 2.73s were available & so no provision was made for them.
Never had a problem with 3.08s.
Just something else to keep in mind, it COULD happen!
