I saw a tech remove a stuck cartridge by using a credit card. Just push the card under the lower edge of the cartridge on the left (or was it right) side. It should pop out. See if that will do it.

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'06 X5 4.8is, TiAg/black, cold weather pkg., comfort seats
'07 750Li, TiAg/black, sport pkg.
'05 Ford F350 silver met./slate gray, Lariat, 6.0 PSD, CC, DRW, FX4