One way to avoid overtigheting is to install a rubber washer/gasket between the nut and the air box and then tighten it. That way, when you begin to get into the overtighten range, the rubber will start to compress/deform and take the excess load.

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1986 300E (3/2002) Rear ended and totaled (10/2009)
2000 Xterra (5/2000)
1992 400E (11/2009) -Sold
1986 300E (12/2009) - Sold
2004 E500 Wagon (6/2013) - Sold