Ok folks to start with it is a beautiful product. Few things to note 
1) if you are looking for (L or R) orientation figure it out ahead of time .. the instruction set talks about it in step 18 . That should be step 1. When you start . It starts with the credenza top .. where the desk sits .. so the orientation of it is to be figured out ahead of time ... 
If you do make the whole credenza up and realize orientation needs to be reversed(DONot try to dismantle it). The glue they give for divots is good. Use a 14 inch drill bit. Measure and make holes on the other end