All tan? Or black quarters with champagne or cashmere rugs? If the latter it’s black. If the former it’s usually black.

Black doesn’t reflect off the rear glass the way lighter colors will in the sun.

i can safely say that I’ve never seen a cargo cover in neoprene as shown in your link. Mine was redone by a then-local friend who took it on as a challenge. She found a partial bolt of the correct fabric as an end lot at a local supplier. The original vinyl edging was carefully unstitched, then hand sewn to the new material through the original holes. Original zipper the same. It’s a Work of Art! I mentioned that there are others who would love have one and that all 928 owners are well funded and appreciate the workmanship. Not a chance! First was a challenge she said. After that it’s an ordeal. She’s in elder care now and doesn’t know anybody anymore. Stubborn/determined Hungarian woman who escaped to the U..S after the war because her dad was a scientist/engineer. Sad to see the rapid deterioration.

I think the original material is a double knit Ponte di Roma, but have never found it in a heavy enough weight.