brake fluid reservoirs per chassis

[floyd111]

I find tons of contradicting data regarding this part on seller's websites. What's the story?
What models/part numbers are for the different chassis?
Are all M110's indeed the same?
I see a VIN split for 350SE, starting 1976, where they use M110 reservoirs (rectangle) up to 1976, and then switch toi the triangle 8V version.
Can anyone solve this mystery?