Well I just had a look at it, what I would do would be the following:

Before you do I recommend to remove both Ethernet kexts from /System/Library/Extensions and the to boot up using -f parameter at boot prompt once.

1. Have the AttansicL1eEthernet.kext placed on some of your locations - likely the Desktop.
2. Right-click it and choche "Show Package contents", then go to "Contents" folder and open Info.plist with you prefered editor.
3. Look up for 0x10261969 and replace it with 0x10631969
4. Save the file, close the coresponding windows and try to reinstall that kext file using KextHelper.

I don't know if changing that ID is enaugh or if the binary file would need changes also, but you might give it a try.

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