Which file does Palette extender modify?

[evobit]

Before Palette extender was available, there was detailed instruction on which system file to modify to add extra palettes.
From memory the line in the file had numbers 1 2 3, and palette extender modfies it with 1 2 3 4 5 6.

Can anyone tell me which file it is??

[jw]

C:\system\shareddata\100058ec.ini

[evobit]

Thankyou kindly good sir