Maybe if you toy with godaddy's advanced DNS, but not from the main domain management pane. You'll get to "create host"
and you'll be presented with a four field form for octets for each host
you'd feed the IPA for your first nameserver to the form for slim, and like to like for shady.
If you create a CNAME record for your second level domain, Iamcool.tld, containing the name of your server you're doing something else entirely
Always check the validy of changes to your domain with DNSstuff.com or DNSreport.com
And pay special attention to the "stealthed nameserver" notes!!! There might be some stuff for your server admin to do
NOdaddy.com - the trauma of bad godaddy