Thats a big help Jeremy , thanks . Spring , Isolator and would imagine a flat washer soldered to the wire . I can go down to the local engineering supplies and have a dig around in their spring box's , if you do have a centre isolator that would be brilliant ,as that would be the hard one to sort out .You can PM me with the cost for the nut and isolator, if you still have the jack and can find a way of sending it without it being a chew on I'll pay you for the lot :-D
Thanks again
Dave