This is the info published straight out of Motortrend.
You can also find and download the Motortrend specsheet off the website too. Note their redline for the 05 Mustang is 6000 rpm and their first gear ratio is 3.34, others have said its 3.38.
Gear - Ratio - Overall Ratio - RPM (Mph)
1st - 3.34:1 - 12.00:1 - (6000) 39
2nd - 2.00:1 - 7.10:1 - (6000) 65
3rd - 1.32:1 - 4.49:1 - (6000) 99
4th - 1:1 - 3.55:1 - (6000) 130
5th - 0.68:1 - 2.41:1 - est(4500) 143
Final Drive Ratio 3.55
Engine RPM @60mph 1900rpm
Hey Fast 05 do you know for sure that you will hit the rev-limiter before 60mph in 2nd gear? I've been trying to find someone who knows for sure for a while now.