Editing with proxies and relinking back to the orignal media

Hello all I know this is going to sound like the most backwards and old school work flow but I’ve just had this job come in for an edit, the film has already been set into a sequence into a rough cut but they’ve used the proxy files to edit with instead of relinking them. Now when I relink them to the original media they seem to work but when I try to attach the proxy files, premiere doesn’t seem to give me that option is there a way round this that can work with out me having to re-edit the film, as you can tell this would be very time consuming for me as the deadline is very soon, if anyone can help out or give advance for a work around this problem that would be great.