[96capricemgr]

Have to replace the differential carrier, talking $500 in parts easy and really I would recommend more do gears while in there even just 3.42s are a nice step.
Even if you leave the existing 3.08s backlash has to be readjusted, taking playing with shims and a dial indicator. A shadetree mechanic can learn to do this but most guys prefer to pay.

Handling will depend on what sort of differential you buy, an Eaton will handle different than Torsen, Auburn like the stocker is discouraged because the clutches are not replacable like the Eaton and Torsen uses gears for torque bias so nothing to wear, shock loads can break them though.