If you want to use this mod in your own compilation, edit it, copy portions for your own use, or whatever you want, that's all fine - I require no permission, no credit, no anything.  I'm only posting this because someone asked me to.

I would've just left Sundy's Post, but he seems to have disappeared at some point, so that one is outdated.

Installation:

• Find your install directory, the navigate to [directory]\nativePC\rom
• Back up the files bbs_rpg.arc, bbsrpg_core.arc, game_main.arc, and title.arc (you can just copy and paste them in place to make [name] - Copy)
• Extract those four files from the zip to replace the installed ones.
• Ruin everything.
  

In case you want to merge this mod with another: the files I have edited are as follows:
bbs_rpg.arc\id\common\font\button_360_0_ID - 0 MIP DXT5 TEX file
bbsrpg_core.arc\id\common\font\button_360_0_ID - 0 MIP DXT5 TEX file

game_main.arc\id\common\cubutton_360_ID - 0 MIP DXT5 TEX file
game_main.arc\id\common\cubutton_360_ID_DE - 0 MIP DXT5 TEX file
game_main.arc\id\common\cubutton_360_ID_ES - 0 MIP DXT5 TEX file
game_main.arc\id\common\cubutton_360_ID_FR - 0 MIP DXT5 TEX file
game_main.arc\id\common\cubutton_360_ID_IT - 0 MIP DXT5 TEX file
game_main.arc\id\common\cubutton_360_ID_JP - 0 MIP DXT5 TEX file

title.arc\id\common\cubutton_360_ID_DE - 0 MIP DXT5 TEX file
title.arc\id\common\cubutton_360_ID_DE - 0 MIP DXT5 TEX file
title.arc\id\common\cubutton_360_ID_ES - 0 MIP DXT5 TEX file
title.arc\id\common\cubutton_360_ID_FR - 0 MIP DXT5 TEX file
title.arc\id\common\cubutton_360_ID_IT - 0 MIP DXT5 TEX file
title.arc\id\common\cubutton_360_ID_JP - 0 MIP DXT5 TEX file

game_main.arc is generally the file edited by gameplay changes, so if you just unpack it, copy in the id\common folder from my .arc and then repack, you'll get PS3 buttons over whatever other mod you've got, easy enough.