Setting TypeGuessRows for excel ACE Driver

I set the TypeGuessRows registry value to 0 in this location:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\14.0\Access Connectivity Engine\Engines\Excel

Is that the correct location where it would be set when creating excel files through SSIS 2012 using the ACE driver like this one:

Provider=Microsoft.ACE.OLEDB.12.0;Data Source=D:\myfile.xlsx;Extended Properties="EXCEL 12.0 XML;HDR=YES;IMEX=1";

I'm still having problems with fields over 255 characters and thought maybe that I had set TypeGuessRows in the wrong location.

Thanks