I have added a few piggy back systems to 2012 and 2013 Malibu boats. If you have a 2013 Malibu you will want both rear ballast upgrades and a little more bow weight. Do you have surfgate?
We can almost replicate the first generation of the Malibu Plug and Play system as the hard tank is the same in boats ordered with and without the upgrade. We would install a 2012+ Malibu Piggy Back but also add a rear drain line by using the Fly High Fat Sac EXV,, Straight Line Sumo 600 or the Eight.3 800 PnP Bag. The install is easy and should not take you more than two hours to install both sides.
As for the bow I would suggest using either a bag in the walk way or up in the bow. If you want to hide it you will need to use lead or a snap cover. The Fly High Triangle Bow sac and Straight Line Sumo Bow sacs work great but we always use a standard Fat Sac and a pump.