Preferred but not required....

So I would like to apply to a PCT job but do not have a license (in Virginia we get a CNA license) but am in nursing school and have done 400+ clinical hours. I would not be doing this as a summer job as I would be able to continue it into the school year and eventually want it to transition to a job (it would be in my top specialty of cardiology). Should I go through the process of getting the license or would my clinical work be enough? I called the nursing recruitment office and they said that while not required it is preferred but wouldn't give me a straight answer of my clinical work had been enough. What do you all suggest I do?

PS. Also I have a cover letter written but it's about 550 words and fits on a page but some people say it's too long. I don't know if it is or not. Any advice on that too?
I worked as a nurse tech-essentially a PCT after 2 semesters of Med Surg clinicals in nursing school. I'm also in Virginia.