solved!
added this to skins/larry/templates/messagepart.html
this in the head
window.onload = function() {
var url2 = document.getElementById('messagepartframe').src;
$('#Fit').on('click',function(){
var tabOrWindow = window.open(url2, '_self');
tabOrWindow.focus();
});};
about line 65
<input style="vertical-align:top; height:3.7em;" type="button" id="Fit" value="Fit to Screen" alt="Fit to Screen"/>
i also (not shown) acheived the zoom in/out functions, but cant seem to reign in the iframe movement.
btw, rc 1.1.6