We found a 1985 Lariat Cluster with a tach. Can we put in our 1984 XLT and what needs to happen to make the tach work?

 

for the tach you need to run a vacuum line.

 

In that case.........aftermarket! Thanks for the help.

 

The tach in my '86 operates by electric pulse from the coil. My cluster looks identical to an '85 that I saw.

Here is a wiring diagram:
http://i608.photobucket.com/albums/t...ricks/tach.jpg

Looks to me to be no harder than hooking up an aftermarket tach. But there are other things to hook up as well like the speedo cable. instrument lights fuel gauges etc which may not be compatible. Maybe you can just swap in the tach part only?

 

I hope it is not like the optional instrument cluster with a tach' for a 1978 Mercury Couger XRT I once had. I optained instrument cluster that had one but the job of hooking it up was such a pain I sold it. It turned out they used a different wiring harness for car equiped with a Tach. The locations of the plugs was different and I would have cut and add wire to the harness behind the instrument cluster in order to relocate the plugs so they could plug into the optional cluster. For that old and long gone bomb is just wasn't worth it.

I accures to me you should be able to get a new instrument cluster for your 1984 with a tach from. http://www.lmctruck.com/ford_truck_cat_page.htm