Well actually, the infectus does support read/write of the Hitachi flash, you just use the Globe360 emulation mode and then select Flash Commands -> Xbox Chip. Then you have to click in the main window and type "enable" to enable the debug features. This gives the user the possibility to write the flash, so just erase and blank check the flash before programming it. Of course you have to dump your flash first and all that, just select Flash Commands -> Read (While you have the "Xbox Chip" option selected, otherwise you will just dump the infectus flash). I just used this to resurrect my Hitachi 47DJ after i managed to kill it while testing out my code. I assume this will work on the 79 to since they have the same flash type.
And regarding the diagrams, here they are:http://www.infectus.biz/diagrams/Infectus_diagrams_LG_Hitachi_v1.1.jpg