Yes, you would take the stat as it is for Defense, and multiply the stat by 1.1 rounded down for Special Defense.
However, note that if you have no EVs in Special Defense, the difference between 31 IVs in Special Defense and 0 IVs in Special Defense is about 6.2%, and this only gets smaller if you add EVs. This is roughly the equivalent drop in total special defensive ability of a 31 HP IV vs. a 16 HP IV (assuming you max Shuckle's HP EVs, which you always should), and those HP EVs also benefit defensive ability. What I'm saying is that on Shuckle, HP IVs are massively more important than Defense IVs.