How hard is it to remove the standard pulley on a factory supercharged V6 (L67) for a mechanical novice?

If you take your time with the pulley upgrade installation process you should be fine. However to be able to best determine the level of difficulty for you to embark on this work, please refer to the fitting instructions in the link below:

http://www.maceengineering.com.au/WebRoot/ecshared01/Shops/mace/4E1D/A79D/D800/6FA9/364C/C0A8/D240/1463/PULLEY_INSTALL_instructions_pdf.pdf