Weighing my options

I currently have a 1973 Dart with a 360 Auto. But was thinking about good 383 Big Block probality Auto. right back. But would my passing gear linkage still work, if i keep it? Would i need to change torsion bars I guess what i'm asking is if i was to make the switch what would i need or would it be better just to stay with the 360 and build it? I just like the ideal of a Big Block in a small car. I appreciate any help Thanks.