Rails Elements for comparison selects

I'm trying to find out what select elements would be best to use for
comparison statements between two objects. Overall, the objects belong
to the same table using the same id structure.

A person would have to visibly select one object and then another and
click a submit button. I'm not sure which would best translate for this
particular application.

There are a possible 120 objects to select from so dropdowns might
become cumbersome. The same could be said for checkboxes.

Example Scenario:

120 teams (select # one)
120 teams (select # two)

Teams can't be the same so perhaps some ajax functionality to not make
the second selector enabled or visible until the first is checked.
Then, remove team from select one out of the select two list.

I could probably use ajax to render a partial for each or start with one
select visible and render the second partial for the second team select.

Which still brings me to my options? How to select a team. Through
checkboxes, dropdowns, search boxes, etc.?

What are my choices and what advice do you think I should follow for
this particular implementation?

Thanks.

If the team names are well known, I'd go with an auto-completing text field.

-philip

Phillip that's a really good idea. I was looking previously at dynamic
ajax observers with select dropdowns but I just don't like dropdowns.

I hadn't thought about auto-completion..

Thanks. I'll post back if I have any questions.