Last year for an optional tach was 1981. So the answer is no. Will a previous tach cluster work, sure. The fonts on the faces changed a couple of times. The 1981 tach should match. I would get the whole cluster though.
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Chris Lucas
1973 Chevy C-10
1975 Chevy Silverado
Captkaos' Page
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Chris Lucas
1973 Chevy C-10
1978 GMC Jimmy (2WD) - SOLD
1987 R10 twin turbo LS
1991 R3500 SRW CrewCab
1985 K5 diesel swapped project
1989 K5 2WD conversion w/ Vette susp Project
Captkaos Customs
73-87chevytrucks.com