Okay, I have my 70 Charger R/T and here's where I'm getting stuck. Ultimately, I'm planning on installing a date coded Dana 60 rear, 4:10 gears and the 440 will produce approximately 500+ hp -- just depends on the $$ situation at the time. I have access to plenty of 23 spline 4speeds, but my question is will they hold up in this current setup or will I need to install an 18 spline instead?

Secondly, I would like to be able to drive this comfortably around town. I've seen Passon's 4 speed setup, but have been told that tho it's nice, its just a 3 speed with an overdrive. Anyone have a good solution to this, can you replace the 4th gear in an 18 or 23 spline to allow for easy cruising on the highway? Keisler will not be an option in my case -- i've heard too many bad things concerning their trannys.

Thanks guys