Don't forget that paint can fade with time, particularly metallic types. "Plain" red is also particularly bad, I've been told. Two 20 year old parts that have been exposed to different amounts of sunlight over the years can easily be different colours, even if they started out the same.
But I know that doesn't really answer your question. Sorry.
PS: My V35 Imola is red. Year of manufacture 1983 (although it is all in a 1981 frame now, but that is another story...)
When I bought it, I believe all the bodywork was original. Currently I am working on replacing the fairing. Again. For the third time. One mishap in the garage whilst it was dismantled, and twice fallen off the bloody useless sidestand.
Anyway, when it was still original, there were four shades of red. Not radically, but definitely different. Fairing, tank, side-covers and tailpiece. I'm pretty sure they were all the same colour when it was new, or at least very, very close to the same colour.