I have done quite a bit of search on here before asking this question that has been asked hundreds of times, so excuse the ignorance.
I would like to copy a product to multiple categories at once. The only way I can see being able to do this is in the copy mode, changing the drop down menu to a multi-select drop down list instead of the single option list. Would anybody know how this is done?

This question has come up quite a few times and the same response keeps coming up of Why would you want to and not just link to the product. So I will answer before I am asked. I sell rubber stamps and the same product is used in over 500 different scenarios. The problem is they all have different attributes.
e.g. An architect will not need the same information on his stamp as would an engineer or a Notary Public but the stamp mount will remain the same. The best way for me to do this is to be able to create a template of the product then copy it into multiple categories and then add all attributes as required.

Thank you for any help or insite in advance.

Drake