TOOLS, PARTS, INSTRUCTIONS -- WHERE WOULD WE BE WITHOUT THEM?
VERY, VERY EASILY. (Oops! Have my caps lock on.) I've been using iFixit for year and years. Helped me replace the power inverter for the display on my old Dell 10 yrs ago (so simple and so inexpensive!), before I got fed up with Microsoft (track pad not working & someone at MS actually told me, from his MS corp. e-mail address actually said nothing wrong with trackpad -- all those service packs have permanently altered the computer, track pad will never work again...maybe get, well, something different) and almost did a Jim Morrison on it to post on YouTube, then realized MS would have their lawyers at my door in a heartbeat.
This trackpad was having problem, got the 64-bit screwdriver set (super set, truly superb steel, even lists the increase in torque if you remember that from HS physics). Was able to replace, then re-adjust it till it was JUST PERFECT for me. Also replaced my original battery (2009, was swelling after 3 years!) with help of iFixit and a GOOD battery.
Very, very, very easily!!!
Have a good, clean, clear workspace, the right tools (bad tools are worse than no tools), and good, clear instructions.