I noticed that on the white plastic insert, there seems to be a sort of stop molded in the bottom to prevent the button from being pushed in too far. This is my mock up from a piece of acrylic and just used a pencil for the dowel. I don't have my car yet, so size is just a guess.
Actual piece:
Mock ups:
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2007 E92 328i 6MT-Space Gray/Black Dakota/Gray Poplar w/heated seats-PCD 4/27/07 (SOLD)
2009 E90 328i xDrive 6AT-Space Gray/Oyster Dakota/Dark Burl Walnut w/ZPP,ZCW,Xenons-ED 4/17/09 - Redelivery 5/30/09 (SOLD)
2014 E84 xDrive28i 8AT-Alpine White/Black Nevada/Silver Matte w/ZMV,ZLP,494 - DD 3/14/14 (SOLD)