81+ tach wire firewall location

[Morgsie]

Does any one have any pictures or info on where the tach harness goes through the firewall on the 81-87 trucks? I found a pic for 73-80 and it looks like it is to the right of the cruise control hole in the firewall (from inside the cab). also, anyone know what size hole it is?

[Corts60]

If you click on my 86 suburban link in my sig, I think the last page shows where I added the tach wire through the firewall. This wire and grommet came in the kit I bought from LMC with the tach conversion. I want to say the hole is half inch.

I think factory tachs were no longer an option after around 84? So an early 80’s truck owner may have to chime in.

[Keith Seymore]

Originally Posted by Corts60

If you click on my 86 suburban link in my sig, I think the last page shows where I added the tach wire through the firewall. This wire and grommet came in the kit I bought from LMC with the tach conversion. I want to say the hole is half inch.

I think factory tachs were no longer an option after around 84? So an early 80’s truck owner may have to chime in.

My 87 has the factory tach.

(No pictures, though)

K

[Morgsie]

Originally Posted by Keith Seymore

My 87 has the factory tach.

(No pictures, though)

K

Keith I was hoping you'd post as I remember you talking about tachs many years ago. Does the picture I posted seem like the correct spot for the later squarebodies? There is a cut out in my firewall pad next to the cruise control hole, I am thinking this is the correct location...

Cortes, I found the pic in your suburban thread, thank you.

[Keith Seymore]

I'm not finding any pics and it's covered up right now, so I'll take a look next time the cover is off.

That does look correct, though. I'm keying off the shape of that grommet moreso than the location in my memory.

K

[Morgsie]

thanks Keith, keep me posted!