gear change....possible gain?

I want to say; You cant just throw gears at it and hope something sticks. But that sounds a little condescending.So how about this; I wouldnt ju......
I would Gear for the big-end.But thats not saying much either. So how about this; The standard reply is gear it to put the car on the line,about 300 to 400 rpm past peak horsepower.
But,you say, I dont know where my engine peaks! Well youre screwed. Take it out, put it on the dyno and find out. Not. Kidding again!
Theres at least two ways of figuring that out, or at least getting close.
#1), if its a streeter, and you have a common combo, a simple guestimate will do. Afterall the gear ratio jumps are about 5 or 6 %, and 6% of 6000rpm is 360rpm,so close is good.But..
#2) if you want to be competitive, you'll need to be right on. So get yourself one of those windshield mounted accelerometers, and learn how to use it.They can be a real eyeopener.Dont get caught up in the numbers,right off. Just find the peak and the rate of decay after the peak, then gear the car accordingly.
Theres other ways,too, if you need to research it.
Lastly, I agree with whats already been posted; that is,throw those 4.10s at and see if they stick. Hah