righty-o thanks pal i'll try that

First, the extended spawnmenu from the workshop is required! Download the content from the link. This content contain the materials and the models folder. Create a new simple file in garrysmod/addons. There must be no special characters in the folder name!
Try this: SWFO imperials. Copy the downloaded files(materials and the models) into this new folder.

.../addons/SWFO imperials/
-materials
-models

In gmod, you start a new game, when after loading the map, search the steam workshop content, and under this you see the Addons - Legacy tab. Now here is your new folder.

how you managed to do get the models i did the guide you said, but idk if it is working