I have a 1GHz 15" with some screen smudges, so I want to swap out the screen anyway. I have a non-functioning 700MHz G4 that will be the donor.
The iFixIt teardown getting to step 8, that is NOT the screen code you need (it appears to match the serial number). The panel code is under the foil.
Step 9 says to remove the 4 corner screws and the screen will lift out. Mine did NOT, as it was double-sided taped in. Putty knife and lots of prying.
Then peel back the foil from a few edges until you can see the real panel code.
So, the number from my 700MHz G4 15" donor is:
LG Philips LM150X04 (B3)
I will see if the 1GHz model is the same when I disassemble that one.