Hi, Doley and Gray (you did not tell us her name), welcome to the forum and thank you so much for worrying about her stress! Stress is inevitable in captivity and avoiding any extra strain is the best we can do for them (keeps them healthy -stress depresses the immune system and stressed out birds get sick more often), especially for grays that are naturally high-strung birds.
Now, first of all, yes, we can help you. Michael has instructions on how to get a bird used to being toweled and here is the link for it:
http://trainedparrot.com/toweling/But, secondly, you might want to use a different perch for roosting (the one she uses for sleep) that would wear down her claws (I recommend Sweetfeet - don't use concrete or sand, please, they hurt their feet) as well as natural tree branches (and I am not talking about manzanita as it does nothing for their nails, I am talking real natural branches, with the bark on them) AND you might want to re-evaluate her diet so her nails don't grow at a higher rate than normal.
Let us know if there is anything else we can help you with.