How to render individual radio button choices in Django?

I think the simply looking at what's available inside the for loop of a choice field will tell one what they need to know. For example, I needed the value to set a class surrounding the span of the option (for colors and such):

<div>
    {% for radio_input in form.role %}
        {# Skip the empty value #}
        {% if radio_input.choice_value %}
            <span class="user-level {{ radio_input.choice_value }}">{{ radio_input }}</span>
        {% endif %}
    {% endfor %}
</div>

There are several attributes as you can see that keep you from having to use the ordinal.

Django 1.4+ allows you to iterate over the choices in a RadioSelect, along with the lines of

{% for choice in form.pc_type %}
  {{ choice.choice_label }}
  <span class="radio">{{ choice.tag }}</span>
{% endfor %}

I'm not sure if this change allows you to use the syntax you describe ({{ form.pc_type.0 }}) — if not, you could work around this limitation with the for loop above and a tag like {% if forloop.counter0 == 0 %}.

If you're tied to Django < 1.4, you can either override the render() method as suggested or go with the slightly-more-verbose-but-less-complicated option of building up the form field yourself in the template:

 {% for choice in form.pc_type.field.choices %}
   <input name='{{ form.pc_type.name }}' 
     id='{{ form.pc_type.auto_id }}_{{ forloop.counter0 }}' type='radio' value='{{ choice.0 }}'
     {% if not form.is_bound %}{% ifequal form.pc_type.field.initial choice.0 %} checked='checked' {% endifequal %}
   {% else %}{% ifequal form.pc_type.data choice.0 %} checked='checked' {% endifequal %}{% endif %}/>
   <label for='{{ form.pc_type.auto_id }}_{{ forloop.counter0 }}'>{{ choice.1 }}</label>
 {% endfor %}

(choice.0 and choice.1 are the first and second items in your choices two-tuple)

The rendering of the individual radio inputs is handled by the RadioSelect widget's render method. If you want a different rendering, subclass RadioSelect, change the render method accordingly, and then use your subclass as the field's widget.