Remove the existing front plate from the case and install the new front plate in its place.
Remove the hard drive tray and PCIe riser bracket
Remove these 5MM standoffs and lift the case so the screws fall out from the bottom. Set screws aside for later.
Bend tray at marked line until parts separate
Install hotswap bays to bracket using the included screws
Install tray in system
Install the 2nd half of the bracket as shown
Using the screws from the standoffs removed previously (or spares from the accessory box), install screws up through the bottom of the case to hold the bracket in place