Inside the
rear bumper.
The former solid bumper blocks are replaced by a forward-open moulding, open steel armature, upper/lower clamping strips, rivet-layout comparison and four body-fixing references. The rear panel, tank and suspension retain their existing datums.
Inspect the mounting relationships
The moulding wraps around an open channel and its estimated mounting faces. Four drawing studs extend toward the rear closing panel, through four separately estimated panel apertures to washer/nut envelopes. That common pattern explains the reference relationship; it does not establish fitted hole centers, threads, bearing contact or tool access.
Keep early and later armatures distinct
Factory PDF p. 269 lists BHM539 rear bar/moulding architecture, CHA244 armature before CHA536 from GAN6-158716, CHA252 upper and CHA253 lower clamping plates, 28 CHA307 rivets and four body nuts. Neither armature is identified as fitted. The 28 rivets are a catalog layout count; their modeled pitch and form are estimates, not a survey of this bumper.
The rear reference follows that rear-specific plate. Front support tube/spring arrangements are not transferred to it. Earlier rear reinforcement details on PDF p. 268 finish before GAN6 and are not assumed fitted. PDF p. 271 also distinguishes number-plate applications, including an except-North-America bracket branch; those generic supplier brackets are not installed in this North American reference.
Owner evidence and estimated station
IMG_6329 and IMG_6341 support the visible rear rubber bumper and corner-wrap context. They do not expose the hidden armature, rivets, body fixing pattern or measured bumper/body stand-off. The new main moulding center is Z −2.18 in the nominal body drawing, replacing the former thick slab’s estimated station. This is a provisional assembly pose, not measured clearance or an overall-length specification. The rear body panel is not moved to obtain fit.
All profiles, sections, moulding thickness, rivet pitch, fastener forms, mount faces and body holes are estimates. Separation exposes moulding, strips and armature; offsets do not establish rivet release, safe bumper support, body reinforcement access or a removal sequence. No impact strength, towing/lifting use, clamp preload, setting force, rivet reuse, loaded contact or verified withdrawal path is established.
Native reference files
Construction checks cover positive valid solids, STEP round-trip, an open moulding mouth with its rear face retained and the four estimated panel openings. Passing checks do not verify fitted geometry or safe service. The source body/tank/suspension and other native exports remain unchanged except the declared panel apertures.