2 barrel to 4 barrel

Remember that a 4bbl and intake can be done for 2-3 bucks total, whereas gears and high stall converter is a 1200+ dollar upgrade
Rear end alone can cost quite a bit, probably will have a 7 1/4, so depends how you go about it, can end up upgrading everything in the back. $$$$, plus it's a fairly big job for some. Plus in the end of the day most will be lucky if they go as a deep as 3.55 gear set.