For my old Grand Prix, I just called into my local GM dealership, gave them the VIN off of the car, and they were able to tell me what features my car came with.
On the same subject of my old GP, it, as it turned out, did not come with factory keyless entry, so I went to a Wal Mart and bought a Bulldog Security Keyless unit. It was simple to install, works great, there website
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has many helpful things on it, and theyhave toll free (at least when I did mine) tech support. But, I am sureothers can think of much better keyless units. The one I bought, did havestarter immobilizer, but I did not hook it up, and with the GP being a '91,no one really wanted to steal it anyhow. :-P
If you want a cheap alternative go to "Walmart" they've got el~cheapo kits that can do the job. If you want someone to put one in for you, check a local car stereo shop.
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