Here is my code. It assumes a lot of things.
save=plotSScreen+200That is it. I'm sorry for the weird format. I copied it by hand from Mimas.
;don't judge my save area - I will find a better one later
;It is safe as long as I don't pull up the graph since the homescreen does not affect it
BCALL($4F66) ;sets the hook
ld a,32 ;I did some experimentation and that seems to be the default value
All this code is for testing. I realize how poorly it is written.