Just finished my Elephant Mod for San andreas. Including custom sounds and animations.
Horse's script Author and Default animations: niki4
Edited Script,Custom Animations,Custom Sounds
and Rigged Elephant Model: Diego4fun
Drag and drop "D4F Elephant" folder into Modloader Folder.
Including 3 skins for you to choose.
Add them manually to your gta3.img file using img editor
and drag and drop D4F Elephant.cs and Sounds folder into your Cleo folder.
Type: d4fele to spawn the elephant
ENTER/F - get down/climb on a horse
W - Forward
S - stand on the rear hoof
A - Left
D - Right
W + space bar - jump quickly