Installing springs is pretty simple on our cars. If it's your first time installing them period the first corner will take the longest.
I'd estimate ~20-30min a corner to remove and install the springs, provided no caliper bolts are stubborn, etc things like that.
Read this guide, it's pretty good and I followed it the first time I did my springs.
Installing Mustang Lowering Springs - Mustang Evolution
Unless you have the equipment setup in your garage, I would leave the alignment to the professionals.
12 Black GT500 SVT PP l 2.6 Pulley/Idler l Airaid l o/r X l 305 NT555R's l Recaros l
04 Azure Blue Mach 1 / 03 Sonic Blue 3.8 / 14 Sterling Grey F150 FX4 402A 5.0 / 11 GT500 R.I.P.