If you do not have the time or money for an engine swap, A re-gear is not for you. Unless you have 3.42s and find a smoking deal on a factory 3.73 front and rear differential (wrecked truck or something) and swap them yourself, It'll cost a fortune to get new gears and have them set up properly. PROPERLY is key here, otherwise they will sound like a pack of coyotes going down the road and will permanently damage the gears and the bearings. You can run a aftermarket carb intake with a tbi spacer/adapter that would probably help a little, along with a total tune up, and the tbi mods. The intakes are slightly different, but any non-vortec intake can be modded to fit your heads with a die grinder and a bur bit.
Exactly what i was gona say and engine swap is cheaper than a re gear