like stated the face plated route is the way to go, its much more street and downshift friendly. last time i did one they were not able to faceplate second yet so i only had it on 3&4. their super easy to work on if you have a press.

68 Dart GTS "HEMI" 10.30 @ 131 pump gas street car 3780#
69 Roadrunner 511 six pack 10.92 drive to track street car