What should be taken into account when disassembly rear bumpers?

Good evening and nice WE together !

Kann mir jemand in kurzen Stichpunkten sagen, was beim
Attention should be paid to dismantling the rear bumper by turning clips instead of pulling nipples here and there break off,
Order etc.????
I wanted to install a Rameder-AHK. The first one will be a long evening event. Silencer has to get out and if I'm unlucky the CD changer, there's someplace where the screws come in.
Does anyone know more??
Thank you very much!
Sven

PS : 2000 optics for 19,50 worked great, I got the tip from the forum archive. Photo is still coming, so my good old C4 still needs to be removed.