[Goober]

Keep the box and install a 6,000 rpm pill. If you max out on HP/Torque at 5500, you don't need any more. I have friends that have blown engines, chevy and ford, buy installing higher than required pills in their box. Most good drivers can get a gear on the money, but you have to consider missing a gear, return spring breaking and other little gremlins that happen. This little box and pill can and will save you thousands.

Just my 2 cents
Mark