I've checked the pictures, but I'm lost. It's way different for the monochorme. It would be easier if someone made a pinout of the lcd.
But i'm correct when I say I need to invert 4 lines? Or there are only 2 like on gb? Or there are more?
And from the 74HC04 datasheet:
"]The 74HC04 provides provides six independent inverters with standard push-pull outputs. The device is designed for operation with a power supply range of 2.0V to 6.0V. "

The connector has18 pins. So far i've got:
2=-6.9v
3=-6.9v
4=1.5v
5=9.9v
6=9.9v
11=3v
12=gnd
13=3v
17=1.5v