[Zope] Templates

Hi, I'm trying to figure a way to avoid splitting "master" templates in two files. F.ex the standard_html_header and footer is splitted in two parts, making it "a little" more difficult to manage. I'd like a solution (probably a class) where I can create a new document, and then base the new document on a single template (like to have a combo box in the document properties where I can select the template). So instead of referring to the template in DTML or TAL for every document, I just change it with the document property. Is this possible (sure :-) ? But if it's not to much to ask for - how (any guidelines appreciated) ? Regards