oil level sensor question

ok its time for my oil change and time to replace my oil level sensor..i picked one up at the local parts store. i have a 96 sts. its an aftermarket part made by standard auto parts. the original part is made of metal and my new aftermarket one is plastic? also i noticed the thread on the new plastic one is longer..i threaded it in a little and it felt like the plastic was cross threading a little so i pulled it back out and im wandering if this is the right part. the description says its for a 96 seville...but thats not always right. the part cost me 40 bucks! ugh! has anyone replaced one of these with a plastic one before or did i get the wrong part?? i should have gone to the dealer to begin with...but the parts department was closed by the time i got out of work:banghead:

Yeah, that's why I'm always weary of aftermarket parts. With something like that if you really don't feel comfortable with it, it's sometimes worth the piece of mind to buy the GM part. If that plastic one cracks, or falls apart, you're going to be loosing oil FAST! I don't know if it's worth the risk to save a few bucks. Of course, it could be fine, and never fail, but it's a risk.
Also, for cheaper GM parts than the dealer, try www.gmpartsdirect.com, www.gmotors.com or www.rockauto.com .

Good luck!

F.Y.I.
i ended up stopping at the dealer. i asked the parts guy to look up and pull the part to compare it. it has been changed to the plastic unit and the standard motor part one was identical to the new factory replacement. i guess they changed over to the plastic threaded one to avoid stripping the threads on the oil pan. anyways its changed out and no more annoying "check oil level" warning at every start up.
thanks for the links i will check them out for future purchases.

Well, that's good to know!