btw - bmp files aren't web complient. Try converting them to jpg, png or gif. I'm such a Natzi.
Generally, people have been letting the Pet window do that job of showing the Full Pet_HP bar.
However, it's not a hard fix at all. It's just a matter of uncommenting a couple things from the PlayerWindow within the Pet_HP gague call. And moving it down a bit.
Only one draw back, the Pet_HP gague is designed to auto-vanish when you don't have a pet. There is no way to stop it, if it's located within the PlayerWindow.
I'm sure somebody can whip something up to suit your desires. Unfortunatly, I'm already pilled up with requests from friends, guildmates and off my website, there's not much time for me, or else I can do it.
Cheers