Can a 350 small block fit in Ford Ranger?

No, a 350 small block Chevrolet engine will not fit in a Ford Ranger without significant modifications, and those modifications would likely be extensive and impractical. The Ranger's engine bay is simply too small to accommodate the 350's size and width. You'd need to modify the firewall, possibly the frame, and likely fabricate custom mounts. The cost and complexity would far outweigh any potential benefit.