Good day. Hoping someone could advise, found a 2nd hand rear diff off a GLA 250 4 matic 156 chassis, i would like to know if it will fit and work in my A 45 AMG (also a 4 matic) 176 chassis, the parts look the same but unfortunately there are no diff numbers, even tried a Mercedes Benz dealer and they could not find any diff numbers on either of them. I dont want to purchase the other diff unless i know it will work (no refunds). can anyone please assist. Thank you in advance.