2 - 4 horas
I wanted to add an SSD and add a faster drive to the mini.
It went amazingly well minus a missing step in the video tutorial. There was not a mention of removing the silver pin under the plug for the power supply before twisting. Had to look up another iFixIt tutorial to figure this out.
Firstly: make sure you plug everything back in. I didn't seat the fan correctly and freaked out at how hot the machine got.
Secondly: Really consider putting in a 7200 RPM drive. Its blazing fast, but does increase fan noise and ambient heat considerably.