I have been searching for info on the alloy exhaust heat shields.
The "Holy grail" shows no paint and I noticed that most people restoring have them bead blasted.
Having a ship-building background I find it difficult to believe that MB would connect/rivet steel stand offs/mounting thimbles directly to aluminium because it would immediately cause electrolysis when wet. Maybe the steel mounts were zinc plated and the alloy was anodised before riveting.
The front heat shield removed from my 230sl shows signs of pale grey anodising, of course the zinc has completely disappeared from the mounts.
As the centre shield does not have riveted attachments and is screwed directly to the floor the problem is less evident.
I will attempt to attach photos of my front heat shield, Note I have given it a light handed stainless steel brush and the scratches against the "coating" are evident.
Can anybody shed a light on these please.
