Make sure you have Lenny's Mod Loader installed, once installed drop every file into E:\Steam\steamapps\common\Red Dead Redemption 2\lml\stream

Credit to RedMaxBR, SergeantJoe, AClassySliceOfToast & DuPz0r, you can find each individual mod below, 

RedMaxBR - 

Chuparosa: https://www.nexusmods.com/reddeadredemption2/mods/794
Railroad on Mexico: https://www.nexusmods.com/reddeadredemption2/mods/882
El Matadero: https://www.nexusmods.com/reddeadredemption2/mods/894
Casa Madrugada: https://www.nexusmods.com/reddeadredemption2/mods/903
Escalera: https://www.nexusmods.com/reddeadredemption2/mods/908
Camps in Mexico: https://www.nexusmods.com/reddeadredemption2/mods/914
Butter Bridge: https://www.nexusmods.com/reddeadredemption2/mods/915
Minor Constructions in Mexico: https://www.nexusmods.com/reddeadredemption2/mods/927

AClassySliceOfToast - 

Camps in Mexico Expansion: https://www.nexusmods.com/reddeadredemption2/mods/917
Frontera Bridge: https://www.nexusmods.com/reddeadredemption2/mods/860
Sidewinder Gulch: https://www.nexusmods.com/reddeadredemption2/mods/836
El Presidio: https://www.nexusmods.com/reddeadredemption2/mods/847
Laguna Borrego Camp: https://www.nexusmods.com/reddeadredemption2/mods/827
Irish's Shack: https://www.nexusmods.com/reddeadredemption2/mods/823

DuPz0r - 

Ramita De La Baya: https://www.nexusmods.com/reddeadredemption2/mods/806

SergeantJoe - 

Mexico On Minimap: https://www.nexusmods.com/reddeadredemption2/mods/872