Where do you find clean 1.52 files? If you have a friend with a non-updated copy, or if you previously backed up your own, you’re set. Otherwise, certain modding communities host “downgrade patches” (use with caution).
If you already own GTA V on PC but your game auto-updated past 1.52, you simply revert via Rockstar’s official channels. However, here is the closest legal workaround: download solution for gta 5 version 1.52