ok i need help asap so if you know what your talking about and can help me out thanks

ok im installing a simple 3 wire hook up shift light (power, ground, and tach signal wire) the easy way is for me to splice the wire right before the ecu, i just cant figure out wich wire it is, if you have pics of a b18 ecu, and can circle or point out wich wire it would be it would be so awsome if not then i am screwed and otu of a cigar lighter in my car cuz thats where the light is mounted

 

i know you can grab the tach signal from the blue wire on the distributor. make sure you test this wire by using a digital multimeter that is set to AC voltage. it should read about 1-6 volts, and should go up with the revolutions. i believe you can get it inside(you should be able to) the car but i am not sure of the color at the ecu. btw, what year is your car?

 

its a 91 ls 5spd, i dont have a multimeter, and on my distributor wich blue wire there is a blue wire on the top of it next to another wire i do belive to be black and yellow and then the only other wires that ive seen that come off it its kinda in between the top and back side of the distributor but thats a plug... and i want to keep it looking clean so wiring from the insde would be the best but i can get from under the hood, just need to be sure

 

look underneath your hood by the latch right near the firewall there is a blue wire that goes into a plug then stops hook it right to it

 

blue wire distributor or 16 pin gray plug near stearing column.