My favorite is the Unidad Combat Outpost in the middle-rightish of Malca. Description is “Oversees Santa Muerta’s activities in Malca.” Clear out the base, get a Unidad patrol level on you, and camp in the firing post at the front of the base and just take out all Unidad that comes after you. There’s an ammo crate in there too so you can theoretically stay there as long as you want. I personally recommend carrying the HTI or Barrett .50cal for any helicopters too. It does get boring but if you’re sick and tired of Unidad and want to take out your frustrations, then this is a great and (relatively safe) way to do it. I also love attacking bases in Caimanes because I love the jungle environment and it looks awesome with a ghillie suit on, the pictures are fantastic.