We have a situation where the customer has a new wordpress website & want's to use the on-line payment processing from the "old" (non-wordpress) site.
My thinking is to modify one of the menu items on the Wordpress site to refer to an absolute url on the old site to get to the payment page.
My question is "getting back".
Is there a generic way to do that without having to know the details of the specific theme, etc.?