Just an observation after looking at probably 2-3000 harnesses from engine, underdash, etc. Most of the factory wrapping tape fades with time, and often gets stained due to exposure to tobacco, the environment, heat, etc. Some factory tape after 50+ years appears dirty, and when cleaned with the strongest solvent, appears shiny when wet but dries to the same dirty appearance.
The cleanest, freshest factory tape I've seen is a tad less shiny than the 33+. When I re-wrap a harness in 33+, it is obvious that it is a re-wrap, as it is too shiny throughout, and doesn't look factory to me. The same goes to the reproduction harnesses: a tad too shiny. I could be biased, though, in that 99.5% of what I see is 50+ years old and it's hard for plastics to retain its original finish after all those years.
