It's been a long time..
Recently I learnt that SAMP made it possible to edit GTA SA textures in custom.img..
Anyway i'm not going to go into details, but I retextured bigear and missionary hill (often /drift3).
If you would like to download them, you can download them here:
(download textures here: http://www.mediafire.com/?j1xydsl0svy0950)
It's only a test, so it's not perfect.
First step, extract the textures from the .zip file.
Second step, you will need some sort of .img editing program. I recommend IMGTool.
(download imgtool here: http://www.thegtaplace.com/downloads/get/552)
Open imgtool.exe, then go "File -> Open", then open 'GTA SA \ SAMP \ custom.img'
Then go "Commands -> Add" and add all of the .txds which you downloaded and extracted.
Then go "Commands -> Rebuild archive".
Now hop in game, you should notice that Bigear is retextured, aswell as Missionary Hill.
Enjoy, and remember, it's only a test. It's not that 'pretty'.