I would look at ordering a replacement line from MB that is already bent and flared and has hardware on it. If you do it yourself, get the right flaring tool and practice making the flares. There are 45* and 37.5* flare tools, most cars use 37.5*. There is an art to flaring correctly. Cheap flaring tools (HF) don't hold the tube firmly enough and let it slip when you push the die on it. Rigid makes a good one, expect to pay $100-150 for good tool. Finally, when flaring the end, make sure you have the nut already in the tube in the right orientation. It's very frustrating to finally make the perfect flare and then realize you left the damn nut off it.
