How to using an existing Metadata set (e.g. ap-trx) for a new dataset/page?

Hello

We have EEC v6.0. I want to create a new page under the payable command centre.

I've created a new page under the Payables application which is easy enough. Gave it a short name "ap-xxxeu-only". I tried to use an exisitng one e.g. ap-trx but it errored saying it already exists.

I then created a new dataset, again easy enough. Assigned the load rules and security rules the same as ap-trx.

Now I need to setup the metadata, but I want to use an existing one e.g. ap-trx. Mainly because I don't want to manually type in every field.