You will have to make very slight mods to install the PIAA 85114 Slim Line. Upgrades from one horn to two. The 2nd needs a wire tapped off the 1st. Ideally what you need is a "piggyback quick-disconnect" terminal. That will provide plenty of hits on Amazon, but heck, you only need 1. I think I saw a small package at O'Reilly Autoparts last week but can't find it listed online.
The Slim Line PIAA is an improvement but is not knock-your-socks-off. Many can not hear.
2018 F-150 XLT SuperCab 4x4 2.7L
2016 Beta 430 RS
2016 Subaru Outback
2013 Tesla Model S 85
2009 Husaberg FE450
1983 Porsche 928S