First, that mod is not for MTA, it's for GTA , but if you want to make it for MTA , you need to replace a models with an LUA script and you must create 'meta.xml'
Check out these two :
engineLoadDFF
engineImportTXD
and here is meta.xml which is required to identifiy the resource.
https://wiki.multitheftauto.com/wiki/Meta.xml