Use Your Network Solutions Email but a Different (Third Party) DNS Provider

On your new DNS host create the following records (replacing domain.ext with your domain, e.g. mysite.us)

CNAME (alias) record 
mail.domain.ext to point to mail.domain.ext.netsolmail.net
smtp.domain.ext to to point to smtp.domain.ext.netsolmail.net

MX record (direct what server to deliver emails to) Priority 10
inbound.domain.ext.netsolmail.net

Hope this helps someone out!