The 10mm are the old ones, the 7.5 are the newer style.

The design was changed to shield more of the surface area of the nozzle from combustion.

Go with the 7.5, it'll save your nozzles.

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1984 300D Turbo - 4-speed manual conversion, mid-level resto

1985 300SD Auto - Runner.


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"If you don't know where you are going, any road will get you there". Lewis Carrol