Yes you have to remove those 2 covers to be able to peel back the carpeting enough to find the locking pump.

The cover #1 for the seat pegs slides forward and lifts off - there are molded grooves that slide along lips on the metal bracket.

The cover #2 for the door sill lifts straight up - there are clips that grab the pinch welded seam in the body below the sill cover. Best to gently start prying at one end and carefully lift it up.

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech