If the puma rear beam
Has the eye type mounted rear suspension and not the fork type then yes you can swap straight over to the fezza this will give you larger rear drums whilst increasing rear ended grip massively..

What engine route are you going for now ? Zetec or sigma engine? escort gti? No parts that I can think of would benefit you if not using the zetec engine, possibly the brakes but I would be going st170 route with 300mm's I have these brakes on a mk3.5 and they're monsters