Problem removing kitchen faucet
#1

I have a two handle faucet that I was trying to remove but one of the locking nuts that secures the faucet to the sink won't budge. I was able to unscrew one them most of the way but the other one moved only one or two turns. I sprayed some silicone on the threads hoping it would help. Does anyone know how to remove these plastic locking nuts? This should have been a simple job and now it's turned into a project! Thanks for any help...