gt90

I have a 1991 300e 4-matic that had the whole rear brake system frozen and rusted to hell. I got the rotors and calipers off but when I tried to take the brake line off the caliper it wouldn't budge, so I tried the other end of the brake line that is connected to the underbody where it meets the metal brake line.
I turned the bolt and the metal brake line snapped.
Now I need to replace the metal brake line on the rear passenger side, the problem is I can't get the brake line out of the T shaped bracket that sits just behind the differential. The bolts are rusted and broke immediately.

I know if I want to get that T bracket off I will have to break all 3 lines off, and redo them. I'm not worried about redoing the rear brake lines but the one that comes in from the front. How easy would it be to replace this line?
does it go all the way to the master cylinder in the front?
I would have to buy straight brake line and bend it by hand.