I free up all of the shafts before selling them. If you zoom in on the pic there is some rust......it's kind of unavoidable on a part pulled from a 30+ yr old vehicle in a northern climate.
If rust free is important you may want an astro shaft?
The 97-2000 monte carlos and luminas did not have the red alarm button......so no guarantees that one would work. Best bet would be to search ebay for a 98 monte carlo fob and verify the back side has the numbers listed in the previous post. I see there are now brand new fobs on ebay.....and...