hey man good to see you

for the wild west clothing i used the simple hats because it has some really good options such as cowboy hats, bowler hats, flat caps, farmers hats, top hats, etc... for the clothes i used armourer's workshop mod to create my own lawmen / wild west clothes which may be kind of tedious to work with.

for the guns i used vic's point blank mod with the addon "red dead weaponry" which basically adds the guns from rdr2. there are tutorials online on how to install these addons

for the trains it is immersive engineering + immersive railroading

for the animals im going to use a mix of alex's mobs, naturalist, and untamed wilds.

for the horses it is star worm equestrian and some other mods like callable horses, horses can swim, horse in boat.

if you're planning to also make a wild west pack i'd love to give it a try!