Swap out optical drive for SSD?

I'm wondering if this can be done to an Envy.
Essentially, they take out the Hard Drive and replace it with a SSD,
then remove the optical drive and fit the prior Hard Drive into a housing
and put it into the optical drive slot.

Install A Hard Drive Or SSD In Your Notebook's Optical Bay : Tiered Storage In A Single-Bay Notebook

On the first page, they mention companies that a product works for but it doesn't include HP. Any ideas?

 

sure it can be done. i used a cheapest chinese metal adapter and the supertalent ssd, the only thing that stock hard drive didn't fit a little bit... the metal parts don't align maybe half a mm in one place near the disc slot..