depends on what gears you already have. it's a very easy swap to do with an 8" rear(if you've got a pre-79 pickup, or a 1 ton or 4 speed) since 4.10 3rds are everywhere. not quite so easy with a 7.5" rear since i don't think any in 2wds came stock with 4.10s(most were more like 3.42, 3.58, 3.73 etc), you have to swap the front ring and pinion from an IFS 4x4.
4.10 gears are a great thing to have in a 2wd though, it'll make it launch harder and put more torque to the wheels.
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