n1netyn1ne

Id go with replacing it..plus new key incase someone stole it..neva know..
-side note-
My key once woulnt go in all the way and wouldnt turn...so i had to strip down to the collum(pretty straight forward) then when the key and lock cylinder were in view ..theres a pin that goes through the top of the lockcylinder that holds it in the collum (mine had to be drilled out becuase the pin wouldnt move)... the new one should slide right in and the pin will lock it in.

88foxbody

alright, i had the same issue, i had my car in my parents barn for like three years and in the time being i lost my key's. you wannan take all the bottom plastic off benieth your steering column, look right under the ignition and there will be a small pin, use a small screw driver or punsh, after you get that out, use a couple flat heads and pull the ignition out, when it is out, there will be a little brass piece in there that you want to get out to, just pick it out with a small screw driver, once that is out.... use flat head to click the gear forward. it will be just like turning your key, power, then start. hit me up if you have any issues, depending on the year of your car you might have to make a little jumper to power up the ecu... because in some stangs the ecu activates when you turn the key, theres a ground in there. if it dosent start, pull the panel off your ecu, there will be a brown plug, run a jumper from the two big pins on the left side, there the only two big ones in the plug, unce you do that run a wire to either one of the pin from the red wire in that plug, make sure you dont pin the black wire, it will pop an inline fuse.. pain in the ***