It started with an iMac, then a Mac Mini and also a iPhone 5 screen replacement.
I bought the iMac maxed out at the time, besides the hard drive. This was an 1TB. I wanted something bigger. Now it's got an Seagate FireCuda 2TB. Also discovered that I could upgrade the RAM to 32GB! Time to buy some tools from iFixit and the parts. Also after not been opened for at least 4 years, it was time for a cleaning!
For the Mac Mini I got an SSD and the old 2x4GB RAM from the iMac. The iPhone 5 got a new screen (bought from iFixit)
Al repairs went smooth. iFixit on the screen and just follow the steps. For the iMac I took my time, but without cleaning and no experience whatsoever with computer installation, I could have done it in 45 minutes.
With Apple there is no 'it almost fits'! It fits or you have to try harder. Oh and the Essential Electronics Toolkit? I couldn't have done the iMac, Mac Mini or iPhone without it!!!