can someone give me step by step instructions on how to install a 5" tach w/shift light under the a/c vents in my 84 z28? i know i have to drill a hole in the firewall but i dont really know how to go about that. should i just drill thourght the plastic right underneath the a/c vents or what. also im not 100% sure where all the wires go. im really clueless and stupid when it comes to this. im kinda intimidated by doing it myself, but i dont want to pay another 100 bucks at the speed shop for them to install it. if anyone knows any urls or has step by step pics and instructions, i would REALLY appreciate it.

 

I know how you feel. Especially when wires are involved. You know where the tach wire to the dist is?

 

i know where to run all the wires except for the lighting wire and the power wire. i just dont know how to go about drilling throught the firewall. i dont want to **** anything up.

 

and the instructions say the red one must be fused before going to a 12v power source and it has to be one that comes on with the key. im retarded with wires.

 

one way is to (after you hook the tach wire to the distributer) go ahead and use the wires going to your existing tach. and there is a light under and behind the center ac vents hook the light wires to it.

 

but how and where do i drill a hole in the firewall? thats my biggest obstacle, and for some reason it seems like it would be difficult to get all the dash parts off to get to it.

 

CHECK FOR EXISTIING RUBBER GROMETS SOMETIMES YOU CAN JUST FEED THE WIRE NEXT TO SOMETHING ELSE ALREADY COMMING IN/OUT OF THE CAB. BUT IF YOU DO DRILL A HOLW MAKE SURE TO PUT A RUBBER GROMET IN THE HOLE THAT WAY THE WIRE DOES NOT GET CUT DUE TO RUBBING AGAINST THE SHARP METAL. IF YOU HAVE AN EXTRA ACCESSORIES SPOT ON YOUR FUSE BOX YOU CAN RUN YOUR POWER STRAIGHT TO THAT.

 

try to find a hole already there if you cn't put it where you want to and deff use a rubber grommet