Just did mine and your post saved me time and $$$. At 1st look under the hood of my 550i I was like oh shyt gotta let the dealers do it but then looked on the forum here and found your thread and DIY. Excellent! 20 mins later and a gentle tug with pressure from an auto trim tool on the rear and both grilles are out and the new ones installed. I went with carbon fiber sport grilles I got from Modbargins. Looks really great! Thanks man.
'12 F10 550i (Dinan Stage 5/Intercoolers, CF Intake, Brace, Shockware, H&R Springs, Eisenmann Race Exhaust, CF rear difuser, Giovanni "Lindo" Graphite 20")
'10 e71 X6 35iDrive SAV (Space Gray) - Gone
'06 e85 Z4 M Roadster (Black Metallic) -Gone
'08 e92 M3 coupe (Sparkling Graphite) -Gone