You shouldn't change the units. Specific rotation in the organic chemistry literature is reported invariably with units:
10-1 degrees m2 g-1
and is calculated from the equation:
[a] = 100a/(c x l)
where a is the rotation in degrees measured on the polarimeter; c is concentration in g/100 mL; l is path length in dm.
The units are archaic, very odd, and rarely explicitly mentioned in the literature. I will now never forget them since I was asked to derive them in my PhD defence. That was fun.
Zainb, there is no reason to change your units, why on Earth do you want to?