Automatic to manual conversion.

Some will complain that it can't handle power but I went this route:

t5 trans swap?
70 Duster T5 Swap
4-speed conversion 67 Coronet

Damn happy with the swap! If it blows up I can stick an upgraded Astro gear set in there, or go TKO 600. Same bellhousing, same mounting dimensions, lots of fun!