I can not make the entire mod FiveM because then this would require me to upload the entire mod.

What you need to do is;
Use the relevant resource.lua I provided.
Make a folder named stream and extract all the files inside the .rpfs to that folder from the original mod first.
Then overwrite them with my own files.

For Addon Props use the same as above with the relevant resource.lua .

Please note that I do not have FiveM, I do not play FiveM, and therefore I can not test if this works or not.
For this reason please don't ask for support regarding FiveM. I simply can't help you.
This instruction and the lua, I provided with very basic knowledge.

Again, if something doesn't work partially or entirely, please don't ask me why. Your guess is as good as mine...