I used to drive a 75 530, the very first US yr for 5ers. Have you looked for the color name sticker? Tell us what it looks like; there were not that many and I know just about all of them. My girlfriends 'was dk blue, but I had abunch of bimmers back then so I probably had a 2002 or bavaria the same color as yours..
Post some pics and for color, try to get one at he end of a door in some good daylight. Polish out a spot the never gets sun and you will have darn near original color for a start.
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