Replaced mine yesterday
Wife was driving down the fwy, saw battery light come on. Got off fwy onto surface streets, got stuck in construction zone. Car overheated and she pulled off the side.
When I got there, the fan was just sitting inside the shroud, the fan belt was loose.
My mechanic made the roadside visit, was able to replace right then and there. The fan bearing housing is as you described, basically a plate with the bearing. The housing just bolts on, then you add the fan. On my 86 300E, he had to loosen a small line that sits above it. He just loosened the mounting bolts, didn't remove it.
He had a special wrench that looks like a slim jim used for opening locked cars. At the end is the stub of an allen wrench for tightening the fan in the small space between the fan and the radiator.
Then he replaced the fan shroud and we were set.
Now I'm driving the car to make sure my wife didn't overheat it too much and did more damage.