In case anyone is interested.
My solution to the OEM boot pulling free/
I removed the plastic piece with the D/R/1 etc completely, reused the automatic trim pieces, both the leather one and the silver trim ring. On the OEM boot, it has holes around the base where it was retained by plastic pins on the bottom side of the manual silver trim ring. I just lined up the stitching front to back and lined up the holes around the inside of the silver trim and marked dots where the holes were. I made sure to keep the holes down low under the faint plastic seam line that you can see when you look at the outside of the trim ring as that part is hidden once inserted back into the leather trim piece. I drilled the holes and used 1/8" dia. Pop rivets pushed through from the outside then fit the corresponding hole on the bottom of the boot onto the stud and placed a small washer over that then cinched the rivet.
The nice part about this method is that you end up with the smooth dome facing outward which when the silver trim ring is placed back into the leather one adds a little bit of tension so the silver ring stays put even better than before. The heads of the rivets do not create any kind of gap, you'd never know they were there.
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2015 370z Sport PW K&N typhoon intake, ARK Grip CBA, plus a growing list of dits and dats
2011 Jeep JK, 2008 Hummer H3 Alpha Sold: 1998 Mitubishi Eclipse