I am building a 67 Valiant with a turbocharged Desoto 352 hemi. It won't be raced, but will be used for a little street scrambling now and then. The car will weigh about 3000 lbs and has a 3000 stall converter. I have 3 different gear sets. 2.23-2.55, and 3.91. The 3.91 is in it now, but I'm not...