Hi, my dad has an HP Officejet Pro 8020 series printer, and he uses it ''a lot''. Does anyone have any tips for getting more usage out of each ink cartridge (i.e. bypassing the sensor in the cartridges that falsely reports that they are out of ink)? I'm completely fine with tweaking the firmware, or whatever I have to do, but I just don't really know what specifically I would need to do. Any suggestions?