Automatically copying posts across multiple wordpress sites without Plugins

We’ve got about 18 WordPress sites and we have a newsletter that comes out on one of them (it’s dedicated to the newsletter and that is all that is published on it). We want to have that newsletter automatically be posted across all the WordPress sites when it is posted to the main newsletter site. Additionally, we need each site to keep it’s own look the entire time (can’t just be a link back to the newsletter site, needs to look like that was an original post on that site). Our web admin is anal about us using any plugins, so I have to code my own, and I’m not really much of a coder.

I’ve tried doing includes on the RSS feed on a template page, which dumps all the content, but it doesn’t appear in post format (just a big long page with all the posts) and it has some additional RSS info at the top and bottom of every post which junks it up (URLS, site title, etc.).

I’ve also tried using the wp_rss function, which gives me a big list of all the newsletter titles and links back to the newsletter site… which is kinda good, but again, it takes them away from the site they are currently on and redirects them to the newsletter site.

Does anyone know how to do this *without* WordPress plugins which were explicity written for this and would actually make my life easy but I’m not allowed to use?

Sincerely,

Frustrated newb