RPM at 70MPH

You can get a T56 with a different 6th, or it's updated version the TR6060 (what's found in Challengers and newer Vipers). I believe the 6th on those is more like 0.65. I think some older GM T56s were also more like a 0.76 for top gear. I wanted the low rpms, so I sought out a 0.5 overdrive as 6th is only ever really used for cruising on the highway. I figured the lower I could go the better.