59Sprint: Not certain about the length of different torque tubes, just know there are many different lengths. Go to tech tips, look for 'Old Online Chevy Manuals' http://chevy.oldcarmanualproject.com/chevyresto/index.htm
Early parts book will have length of different propeller shafts.

Yar: Would be interested in how you shortened torque tube and propeller shaft. I looked at one with just that intention but passed on the idea as more then I wanted to take on.