MB Quart makes some flush mount/ flush grill speakers that allow use of the stock window crank.  I had Boston 4" now Boston 5.25" speakers in my doors.  I bought a window crank extenders from the now defunct Velocity Sport Tuning and used A2 Golf/Jetta cranks.  The Boston 4" only requires four small holes to be drilled around the original hole.  The Boston 5.25" required enlarging the hole and an additional hole for the tweeter.

Dave
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87 Vanagon GL Wolfsburg
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