title: Magento how do I override/alter template/payment/form/purchaseorder.phtml file
body: <p>I need to add some text to this file [<code>template/payment/form/purchaseorder.phtml</code>], for a particular store within clients' magento site.  When I make a change to the purchaseorder.phtml file, it changes the text on all the stores.  So I need to somehow customize this for one store in particular.  </p>
  
  <p>I have read comments on several sites, some mention changing the local.xml, change the config.xml, make changes in admin panel, but this such a small change, I don't want to disrupt anything by going overboard.</p>
  
  <p>I need to extend the functionality on the backend so this change can be made for a particular store or stores. the sites has five stores built into the one install and for now I need to make the above change to just one store. </p>
  
  <p>I think I need to somehow add a PO field Heading and an "Additional Text" option to the Purchase order section in image two.  is this correct, if so how do I do this?</p>
  
  <p>Could someone point me in the right direction to making this type of change please.</p>
  
  <p><strong>Note</strong>: I <strong>can't</strong> do the create directory structure, copy files, change needed files option</p>
  
  <p>This is magento 1.7</p>
  
  <p><img src="https://i.stack.imgur.com/hmIVT.png" alt="enter image description here"></p>
  
  <p><img src="https://i.stack.imgur.com/ANl5U.png" alt="enter image description here"></p>