get good at shell scripting so you get intimate with the systems better and quicker .. read a lot of books ... browse the forums for interesting questions ... read some more ... and show the admins that you understand their work ...
most places in boston --- from what i gather in the ads --- want an admin with a comp sci or elect engg degree and/or years of experience ... however, they will also interview people with interesting resumes that show possibilities with the jobs they're posting for ... once you get past the resume filters, you can get in once you convince them that you can walk the walk and not just talk the talk ... and you don't really need a CIS or comp sci degree although they can help a lot ...
btw, i don't have a comp sci degree either ... but i can walk the walk in most places ... the other places i stay away --- for now
... and clearances usually only apply if they're related to the job you're applying for ... but having them won't hurt at all ...