You can try capping the line, or using a pressure bleeder, but the risk remains that if you get air in the ABS controller, you will likely need a shop with appropriate tooling (GT1 or equivalent) to properly bleed the brakes. Not sure it is worth taking the risk of replacing brake lines yourself if you don't have the tooling. Why not just pay a shop to do it?

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue