I can't say this topic will interest most people, but I really just want to put my experience out there.
Tonight I finished a "transplant" of a Dell Latitude E7440 from a beat up worn shell into a relatively brand new one.
These business laptops have always been attractive to me since they come with decent hardware, a magnesium chassis, and spare parts are plentiful and cheap. They are used in office settings and then auctioned off at a fraction of what the business originally paid for them, so most don't endure much.
I picked up one of these a month ago on eBay that has an Intel i7 4th gen processor, 256GB SSD, and 8GB of RAM. It must have been used by someone out in the field because it was just a mess externally. The lower chassis was shiny from constant touching, the lid was scratched and dented all over. The keyboard and screen were still quite good, though.
After some agonizing research and shopping, my spare parts arrived today. A newish lower chassis, newish lid, newish palm rest.
I started after dinner and basically dismantled the entire laptop. Every screw, cable, and piece of tape taken off gingerly.
I lost about 2 hours and almost gave myself a heart attack though because one of the display cables was damaged during removal. They didn't really design it to ever be pulled, and in the process some thread-sized wires got pulled out of the connector that's about the size of HALF a tic-tac. It was a HUGE pain to figure out how the connector works and to use a magnifying glass and tweezers to rebuild it. Luck must have been on my side because I was able to get it reassembled.
The LCD assembly was a bit of a pain as well because the bezel is taped to the edge of the LCD, and in the process of removal this tape just became useless. The tape almost looks like woven metal fibers so I have no idea where I'd find a replacement. It provided dust protection, so I'll just have to be careful about where I use mine.. not that I abuse my computers anyway.
Anyway she's up and running..after a few scary automatic restarts (due to recognizing new hardware like the SC card reader in the new palm rest).. but seems stable on Linux Mint Cinnamon. I'll leave it running all night as I had to clean and reapply thermal compound to the cpu/heatsink during the rebuild.
Below pic isn't mine, but it's close enough for visuals.. they all look the same.