on a 2010 Mercury Grand Marquis is the LCM located above the gas pedal.
On the older models it was located between the gas pedal and the radio. You basically have to tear the entire front of the dash apart to get to it. I can't seem to find any info for the 2010.
I think u may b wrong the dealership said it was in the same place as an 03 model. And if u look closely that pic u posted shows it there also.
The pic is for an 03, so I guess your in luck... lol...
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