While wishing you can do it yourself. The necessary pointers are in PGE so take note of those and do itman's tut just change the pointers that he mentioned and you should be good.
It's just that there are more FR hackers than Ruby and Emerald ones. :3
Here's an animation for Bug Bite,
I haven't edited the rocks since the 5th gen Bug bite has brown rock thingies in it too. :3