I know this for a fact. Elon personally has been to Mercedes HQ many times and we are being prepared for a company wide restructuring.
As the first step after acquisition, Tesla is becoming the sole supplier (tier-1 supplier) for the entire Mercedes group. To explain:
Mercedes makes most of the body panels, chassis, frame etc but most if not all other parts like seats, wires, connectors, electronics and so on are made by tier-1 suppliers. The majority of cost is in those parts.
Tesla is buying Mercedes leveraging its current value and making a huge cash payment since Tesla has huge cash reserves.
This way Tesla will siphon off most Mercedes cost as its own revenue and since Mercedes is going nowhere it will cement Tesla as a fixture being tied to Mercedes. Once it's clear that Tesla is going nowhere being tied to Mercedes and its futile to try the attacks against Tesla will eventually stop.
Tesla will also implement EV technology, entertainment system into Mercedes.
This is also giving Tesla access to the entire Commercial vehicle and HGV market.
A lot of companies, trucking and logistics companies have fleet contracts with Mercedes and this is Tesla's in.
It will also give Tesla EU and German government guarantees in case of default/ it will prevent Tesla from ever defaulting.