You could enter a token in your text-titles on the form where you want autonumbering, such as #num#, and then use javascript or jquery to find those tokens and replace them with incremented numbers.
The drawback to this is that if you exported the list to excel, the tokens would not get translated to numbers. But it is a good solution for on-screen rendering.
Use Firebug to figure out the class of the container housing your autonumber tags.
Maybe you could do something like this:
function TokenReplacement(){
var ClassName = 'ms-formlabel';
var elements = new Array();
var elements = document.getElementsByTagName('td');
var numerator=0;
//Now do find and replace on everything else
for(var e=0;e<elements.length;e++){
thiselement = elements[e];
if(thiselement.className == ClassName){
//autonumber the questions by replacing the #num# token
if(thiselement.innerHTML.search('#num#') > -1){
numerator++
var replacenum = "<b>" + numerator + ". </b>";
thiselement.innerHTML = elements[e].innerHTML.replace('#num#',replacenum);
}
}
}
}