Typically, to install piezo saddle loaded tune o matics requirs a hole drilled from teh top of the guitar going to the bridge pickup, and then from the bridge pickup cavity to the electronics cavity
This is not an easy installation...it will involve either drilling holes for the wires from the bridge pieces, or running them through the cavity of the bridge pickup. Not to mention the convoluted elctronics, stereo output jacks, etc. You may want a pro to do it- I wouldn't attempt it, especially on an LP. I recommend the RMC piezos, which sound better than the Fishmans.
Sure isn't a 5 minute job, you need to file a small "U" in the bridge pickup ring base to route the cable from the tunomatic into the pickup cavity and then into the control cavity. If you are going to "blend" the output (ie not use a Y cable to separate the signals), then you need to remove one of the tone controls for the preamp or use a dual concentric pot for the two tones if you wish to keep both available, fit the preamp and find space for the battery.
honestly, when I use my piezo, the only control I need on the guitar is a magnetic/both/piezo switch. I dont need a piezo volume (mine is up all the time) or tone (that comes from the mixer).