I'm looking to build a ground up custom case. It's gonna be a lay down style to go under my TV with my stereo Amp. I have HP tower beats audio edition that suits my regular use. My case will need to fit in ruffly a 20" by 20" and tall enough for a regular pcie graphics card. My main hurdle at this moment is I'm having trouble finding guides for how to mount my hardware into a new case with no mounting plates, racks and trays. I find guides for cases but nothing that points to where I can buy the miscilanious inerds that will hold my hardware in place.