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**hatzie** · 12-12-2019, 11:42 AM

You can use the AT column. The AT lever collar isn't aesthetically pleasing on a MT truck but it will work.

1978-1991 harmonica plugs are the same pinout. 73-77 are different.

1973-1991 Wipers, dimmer, and cruise are separate from the harmonica plug. 73-83 are on the dash and floor. 84-91 have wiper and dimmer switches on the column but you aren't required to use them.

The above is only the wiring. You still have to deal with the steering shafts. GM used a splined and a Double D end on the column. I'm not sure what years were what configuration.

12-12-2019, 11:42 AM	#2
hatzie Moderator Join Date: Oct 2008 Location: Wentworth, NH Posts: 5,021	Re: GM column swap You can use the AT column. The AT lever collar isn't aesthetically pleasing on a MT truck but it will work. 1978-1991 harmonica plugs are the same pinout. 73-77 are different. 1973-1991 Wipers, dimmer, and cruise are separate from the harmonica plug. 73-83 are on the dash and floor. 84-91 have wiper and dimmer switches on the column but you aren't required to use them. The above is only the wiring. You still have to deal with the steering shafts. GM used a splined and a Double D end on the column. I'm not sure what years were what configuration. __________________ 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... 1973-1991 GM Light Truck Service, Unit/Overhaul, Wiring Manuals, Parts Books and Some 1968-1999 GM Service Training textbooks in PDF 1988-1998 GMT400 CK service manual project 1988-1993 GMT400 CK parts books. 1967-1972 GM Light, Medium, & Heavy Truck Service Manuals in PDF Please include at least the year and model in your threads. It'll be easier to answer your questions. And please let us know if and how your repairs were successful. Last edited by hatzie; 12-13-2019 at 08:08 AM.