Nested forms without looping through fields_for collection

Hi,

I have a fairly complex form and I am wondering if it is even possible
to do what I am attempting.

I have multiple models included in the form. A small example would be
the following:

Company has many Locations
Company has many PhoneNumbers… and so on

I have this working without issue using Rails 2.3 and nested forms.

Where this becomes complex is that I also have another model named
Rankings. I allow my users to assign a raking to each of the fields
that are entered. Each model has a has many :through relationship with
Rankings. I wish to send these fields back to the server in a nested
format with the attribute that they belong to, as well as with the
field name that they are being assigned to. I have attempted to use a
fields_for, but it simply loops through the entire set of Rankings
duplicating each of the attributes multiple times.

Does anyone have a suggestion to implement this?

Thanks!