The attchment of the cpu cooler to the cpu would be the thing I would mention as being the thing that you want to do only once since redoing requires the reapply of thermal compound. Since I don't see an after market cooler on your list then I would say your going with the stock cooler and that come with a small amount of thermal compound. So a reapply might require a purchase of more thermal compound.
Even if you don't have a side window the wiring can be important with airflow inside the case so a neat routing of wires will be helpful. A good neat wiring job makes it easy to navigate the insides of the case and you'll be able to see to make sure everything's connected.
Following the guide would give you all the info that you would need and in case it's not mentioned and you have forgotten make sure on first boot thqt you go into the bios a set the boot order even though you have only the one drive.