nes reproduction help

[ATARI7800]

Hi I have a question that I hope some one can answer
ok I'm creating a nes repo that uses a snrom borad nesdev says to solder pin 24 to GND (OE)
where is the ground and what does oe mean??    

[petik1]

Ground comes from pin 1 and 72. No clue what OE means.

[ATARI7800]

heres the link http://nesdev.parodius.com/NES%20EPROM%20Conversions.txt 

[ericj]

OE is Output Enable. What chip # are you using?