subscribe form - subscribing to one list using a radio button

i'm pretty sure this can be done but i cant think of a way yet, having a bit of a mind block and i think the answer may be really simple...

i have generated a subscribe form and have added in the opt-in checkbox for my other lists, however i want to give the user a chance to subscribe to one list only. so basically use radio buttons instead of checkboxes.

in checking out the html code, each checkbox has a unique name, which means you cant just turn them into radio buttons because radio buttons require the group to share the same name?

so how am i to do this? i appreciate the help thanks

p.s were only allowing people to sign up to one list because we don't want duplicates across multiple lists, and yes i know about segments but we cant use it for this client as they require segmented reporting which campaign monitor doesn't yet have. cheers.

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