Edit / Remove custom fields in new responsive theme

I have recently transferred my listings from a DP 7.1.4 site to a new DP Responsive theme.

I used the plugin supplied to export all listings / data and discovered that some information that should be hidden on the listing page is now showing on the new theme which means I have to go through the process of editing hundreds of listings.

I am sure it is simply a matter of deleting these custom fields that worked on 7.1.4, but I can find no place to access hem in my admin panel.

I am quite happy to delete the custom fields and add them again in the new Responsive theme; however will that have any effect on the hundreds of old listings?

Would greatly appreciate any help / advice from anyone who has experienced and solved this issue.

The site is offline until the rebuild is complete however I can send screenshot to anyone able to help.