I think you're better off without it. It takes too long to loosen up the alternator to change the belt with that bolt there. Just leave it off and pry the alternator out and tighten it to get the right tension just like most other sensibly designed alternators work.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13