Respectfully, I think you need to do some more research on the effects of changing gearing.
Going for taller gearing is going to mean you'll be taking off at the traffic lights in low range if there is any hill involved, or else slipping the clutch to an early death.
Most people either stick to standard (3.54:1) ratios or if fitting larger tyres increase the ratio (4.1:1 etc) rather than going for a taller ratio.
Not to mention that you can't easily purchase taller diff ratios for Landies.

