I have a 94 Full size Blazer. It has a manual tranny. It does not have a tach dash it has a shift light. How hard is it to put a tach dash in this? Is the wiring already there?

I have a 1990 GMC c1500 with a 5speed manual that didnt have a tach, so when I installed a cd player, I took out the old radio above the ac switch and I installed the tach in the hole and wired it down through the hole. It wasnt that hard to install if you know how to do the basics of wiring. And to answer your question, the wire isnt alreaddy there, you have to wire it. If you have any questions on how to wire it, contact me

go to this site it has info about putting in a tach dash http://www.fullsizechevy.com/fscu/88-93tach.shtml