Look for a used cluster of guages, not real cheap, but a lot nicer on the wallet than a new set. There really isn't anything else that will screw into that line even with an adapter...... could replace the whole thing from the filter housing I suppose.

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1985 300D Turbo ~225k
2000 F350 (Powerstroke) 4X4, SWB, CC, SRW, 6spd ~148k
1999 International 4900, DT466e (250hp/660 ft/lbs), Allison MD3060 ~73k