Your thoughts on this idea

[Skunksmash]

Ok if I am understanding, an HEI is when the coil is mounted on top of the distributor cap? My coil is off to the side. Just wanted to put that out there in case its relevant to this situation. Dang 87 being different from all the rest of the trucks around here lol

Don't know much about HEI, just read up on it here:

http://en.wikipedia.org/wiki/H.E.I.

[Captkaos]

forgot that yours is TBI.  There should be instructions on how to hook it up that came with the Tach.

[Skunksmash]

Now I need to ask about my fuel gauge. I bought this:

http://www.amazon.com/Auto-Meter-3514-Short-Electric/dp/B000CIJ5YC

Because it reads in the range of 0-90 Ohms of resistance. 0 being empty, 90 being full. (I think...) According to autometer the range for mid 60's to mid 90's GM vehicles is 0-90 Ohms of resistance. As my truck is an 87, it seemed that the 3514 sport comp fuel gauge is what I needed since it meets those requirements. However, for some reason, the needle just stays pegged out a way beyond a full tank of gas. I simply soldered the wire to the corresponding copper contact point for the fuel sender on the printed circuit. It seemed to work just fine for my digital water temp gauge.

[bake74]

     Did you recheck your soldering job to make sure you did not damage something.  Sounded like it should work just fine.

[Skunksmash]

Yeah I'll need to recheck.

[Skunksmash]

I'd also like to see a diagram of the interior fuse box if anyone has one. I'm looking for an empty accessories slot that comes on when you turn the key on. If there is one.

[Captkaos]

On an 87 it will be labelled ING

[Skunksmash]

Thanks a lot man that helps. I accidentally wired up my water temp gauge to only come on when the headlights come on lol. Not very useful. But I do find it odd that they would have an orange wire that they say to wire to your +12v headlight switch, and a red wire that they tell you to wire to your +12v key on power source. Wouldn't you just need the one for the key on power source?

[454Man]

Orange is for the light inside"night time driving"

[Skunksmash]

So theres two separate lights in there. One for the LED temp display, and another that is just some kind of backlight.

[jaredts]

Gages typically have a separate power wire for the backlight.  This is so it only comes on when your dash lights are on (parking lights/headlights on), and also so it dims along with your dash lights when you use the dimmer.  It should work fine if you connected it to the accessory power or twisted it onto the accessory power of the gage, but you wouldn't have the functionality I mentioned.

[Skunksmash]

Ok well thanks again for all the help everyone. But is this the negative side of my coil? I think it is but I have to be sure cause Autometer says you'll ruin the gauge if you hook it up backwards.

[Skunksmash]

I would just check but I got to get a new voltmeter.

[mpullen66]

That is the wire for your tach.

[Skunksmash]

Yeah I always wondered what it was. It seemed odd that it was even there, given that the truck did not come with a factory tach.