4 Speeds and Gear Ratio's

[Hlindeen]

I have been hamering around the idea of two choices.

One - Put a 4 speed in with a differant ring and pinion?
Two - Put in a 5 speed with differant ring and pinion or just differant axles.

Not for sure what i want to do just bought a brand new NP203 transfercase for my 350 turbo trans and new adapter it costed me around 1100 for it. But now wondering about what to do with putting a older redone 4 speed in or go with putting in a 5 speed, i have 4.56 gear ratio and a 355 motor so let me know i need some help with this one thanks!