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**hatzie** · 11-05-2015, 08:59 AM

^^^^ Forgot about the early potted boards. ^^^^
The 73-75 tachs have a different font and no colors on the face... And the $&%* potted board. The usual suspects will replace the board and calibrate from 5K to 7K.
I've seen narrow window 76 tachs with just a seatbelt light in the tach...

The fairly rare late 1980 and later tachs have a different color needle, a light brown ring and, a larger font.

I do believe he has the wrong year tach harness too... Packard 56 instead of Pak-Con I is the thing that leaps out at me. Most of the Pak-Con I fuse panel connectors for the accessory power ports on the ATC fuse panels are obsolete. #12004892 can still be had for this harness... #12004888 directly above this one is obsolete. The clock power connector #12004886 is obsolete as well so don't loose it.

American Autowire has the correct harness with the right connectors but there's no filter capacitor included. They may be doing what I have contemplated for some of the obsolete connectors in their arsenal. 3-D laser resin printer. They are a fairly large business or I bet they had a run of some connectors made. They make many of the, extremely expensive to make, molded rubber connectors for their harnesses like the 67-83 taillight plugs.

The 73-78 harness could be used but it won't plug into the IGN port on the 79 fuse panel or the ground buss bar.

11-05-2015, 08:59 AM	#15
hatzie Moderator Join Date: Oct 2008 Location: Wentworth, NH Posts: 5,021	Re: Add Factory Tach or Not ? ^^^^ Forgot about the early potted boards. ^^^^ The 73-75 tachs have a different font and no colors on the face... And the $&%* potted board. The usual suspects will replace the board and calibrate from 5K to 7K. I've seen narrow window 76 tachs with just a seatbelt light in the tach... The fairly rare late 1980 and later tachs have a different color needle, a light brown ring and, a larger font. I do believe he has the wrong year tach harness too... Packard 56 instead of Pak-Con I is the thing that leaps out at me. Most of the Pak-Con I fuse panel connectors for the accessory power ports on the ATC fuse panels are obsolete. #12004892 can still be had for this harness... #12004888 directly above this one is obsolete. The clock power connector #12004886 is obsolete as well so don't loose it. American Autowire has the correct harness with the right connectors but there's no filter capacitor included. They may be doing what I have contemplated for some of the obsolete connectors in their arsenal. 3-D laser resin printer. They are a fairly large business or I bet they had a run of some connectors made. They make many of the, extremely expensive to make, molded rubber connectors for their harnesses like the 67-83 taillight plugs. The 73-78 harness could be used but it won't plug into the IGN port on the 79 fuse panel or the ground buss bar. __________________ 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; 11-05-2015 at 09:14 AM.