Has anyone swapped out the stock 3:73's? I've read about Fox Bodies with stock Coyote motors and steep gears (4:88 etc) running high 10's in the 1/4 mile. The Boss 6 speed makes the rear gear close to a 4:10 if compared to a Tremec. It just seems like a cheap mod that would not void warranty. I'd really like to try 4:30's with drag radials. Is there a speedo gear to swap out to correct the speed or must it be done by the computer?