I'm running a 9" with 3.89 gears, 26.5" tall tires, T56 with the .80 and .65 OD gears. This ratio is perfect IMO. I can cruise the two lane back roads in 5th gear at 65mph and 2500rpm. Or I can get out on the interstate and run 75 at the same 2500rpm. I think a 4.11 would be too low. I previously had a 3.64 and I felt it was too tall for my taste, I never used 6th gear.
You might also take a look at Roush Used Racing parts. They sell all manor of surplus NASCAR parts including 9" center sections.
http://www.sriperformance.com/Used-R...rain-s/428.htm