You took those hard drives out. Now they have to go back in just right to make everything work again.
Putting your drive or drives back in, conceptually, is the reverse of pulling the drives out [Hack #21] and opening the TiVo [Hack #20] in the first place. But, as usual, there are a few subtle things to get right—we'll make sure to cover in this hack.
The first thing you should do is get your new drive or drives ready to go in. If you are placing only one drive back into your TiVo, it is generally recommended that you set its jumpers into "master." If you are installing two drives in your TiVo, one should be set as "master" and the other as "slave." Also, arrange things so the master drive can be at the end of the IDE cable and the slave drive can be installed in the middle connector.
Use the same four Torx screws to connect the new drive to the bracket that you removed from your TiVo. Take care to put it back in the same way it came out. When installed properly, you will see four bracket holes below the connectors when looking at the power and IDE cable connectors with the drive-label facing up.
If you are installing two drives, you will need that newly purchased bracket. In lieu of a bracket, cable ties will also work to secure the drive so long as you aren't planning to move your TiVo (we can promise you that if you give FedEx your precious cable-tied TiVo, your drive will be surfing all over the motherboard ...