The Brake light gets its' ground from a switch on the combination valve or the parking brake. Unplug the wire from the brake combination valve. Look on the left end of the frame crossrail that runs between and under the front of the engine but not quite under the radiator...
Boy that description doesn't flow well... The round white plastic plug with no wire on top in these pictures.
http://67-72chevytrucks.com/vboard/s...84&postcount=5
Check that the parking brake switch is plugged in and switching.
I'm not sure about the turn signal lamp.
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1959 M35A2 LDT465-1D SOLD
1967 Dodge W200 B383, NP420/NP201 SOLD
1969 Dodge Polara 500 B383, A833 SOLD
1972 Ford F250 FE390, NP435/NP205 SOLD
1976 Chevy K20, 6.5L, NV4500/NP208 SOLD
1986 M1008 CUCV SOLD
2000 GMC C2500, TD6.5L, NV4500
2005 Chevy Silverado LS 2500HD 6.0L 4L80E/NP263
2009 Impala SS LS4 V8
RTFM... GM Parts Books, GM Schematics, GM service manuals, and GM training materials...
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