Remove Category Links for All Products

Hi Guys

I am in the process of upgrading my zen cart shop which contains over 2000 products which have been linked in the website to other categories in other sections i would like to restructure the way the products are listed but to go through multiple categories and remove the link so that the product is only in one category and i can start arranging them easily.

Does anyone know of an automatic may of remove the linked categories and just leaving them in there normal category.

Any help would be much appreciated.

Thanks
Brad

It sounds like a job for a SELECT DISTINCT MySQL query- However how do you know which of all the categories a product is connected to is the Master category???

Currently we have over 4000 products in our shop which would talk a long time to go through and delete manually, is there no tag in the mysql database that distinguishes which is the main category for the product and so just delete the other.

Thanks
Brad