Redirect Certain Pages From https:// to http:// in Wordpress

I have a Wordpress site which is integrated with WHMCS. I use an SSL certificate on certain pages of the WHMCS installation. If a customer returns to the Wordpress part of the site from WHMCS via a menu link an error is generated as the customer is moving from a secure session to a page where not all the content is secure. I need someone to redirect the Wordpress pages from https to http if the customer enters https or clicks back from a secure page to the Wordpress portion of the site. This should be done in htaccess using Mod_Rewrite. This project should be easy if you know what you are doing. Please only bid if you can carry this out quickly and easily.