IMO, just get a new windshield. You are going to pay the same or more in labour costs to have the windshield professionally pulled and resealed (it has to be cleaned up prior to reinstallation) and since it is shotblasted anyway, what is the issue? If you got that many years out of it, it doesn't owe you anything.

Don't do it yourself, nothing worse than a leak or a patch job.

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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