Gents,
You'll find tons of topics regarding this specific subject. Just do a search. But in a summary If you have a torque tube enclosed driveline and want to keep it, you could invest in the infamous Patrick's 3:55 gears which will raise your speed by 15%. Otherwise you change your tranny and driveline to an open driveline which will give you many different choices of combo's to pick from. Do a search on drivelines, Rear end Gears, etc.
I have a '50 and want to keep as stock as possible so I will later this year go with the Patricks 3:55 gearing package.
T Mott, As another bolter said not too long ago keep in mind that whenever someone gives you the finger, they're just telling you that YOU are #1 and salute you for that. Be Proud.