Installation should be done following the instructions included with the new hardware.  If none was included, return to the store you purchased it from and ask for instructions.  If none are available, don't use it.  Return it and find another system.

Most cabinets are 24" deep on the outside and 23" deep inside.  Usually, 22" side-mount slides with back mounting sockets will work nicely.  Inspect the opening and note anything that will conflict with the new hardware.  If you see a problem, explain it to your hardware sales person and he/she will suggest the right system.

Side mount hardware is always more durable and more pleasing to use than single center mono-rail or center bottom mount systems.  If you want to switch from an existing system to another, you will need to build a new drawer box.