Just kinda guessing here, but if the key doesn't turn at all in the ignition then it was improperly made/ground. They didn't grind the same pattern (mechanical key cut as you mentioned in your post above), on the spare key, as the original key. Probably have to get a different one.
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1994 Red SVT Lightning #2019
[This message has been edited by 96GTS (edited 04-27-2001).]