Reinstalling Everything!

Hi. I may have a really dumb question to ask. I am re installing The Sims 3 and every expansion and stuff pack that you guys have made available. I just want to say thank you for that. Some one else had originally installed everything for me and my WA EP wasn't working among other problems. Long story short I uninstalled everything and am re installing. I am following the directions in the ultimate fix and the directions given in the forum on how to install sims 3 correctly to a T! Now for my potentially dumb question. I am installing WA and want to know if I should follow these directions. (I will NOT be applying any cracks!)

"2. Now open the Start menu. Type 'regedit' in the search box and press [ENTER]. Navigate to:
HKEY_LOCAL_MACHINE\SOFTWARE\Sims\The Sims 3 and double-click on 'SKU'. Change the shown
number to 2 and press 'OK'. Close the Register Editor."

Should I do this step before I try to install WA? Or should I ignore it like the forum instructions say to do for LN?

I would appreciate any help. If I am missing something or this is a really stupid question, please for give me! I am brand new to this. Thank you in advance!! :newfag: