[Help] Looking to edit text boxes ORAS, Among other things (input please!)

So... I was around here earlier, asking about how to switch player models. Good news! I got them to work, and I've decided to try my hand at a ROMhack. So far it's going alright, but I have some questions.

• Where can I find the location of the Professor Birch sprite in the intro, and how can I replace the image?
• Similarly, how can I replace the PSS sprite right when you get past the title menu? The one next to your save data.
• And... The little sprite of your head on the...

[Help] Looking to edit text boxes ORAS, Among other things (input please!)