Adding Second RSS feed

Hello all,

Have spent a great deal of time working on this and researching, but am feeling somewhat stymied. Here’s the deal:

I’d like to use the RSS feeds from each site to populate a site outside the network (not the most efficient, but it’s a phase one thing). I need the RSS feed to be full and not excerpt, but don’t want to take away the ability of the site owners to choose what their feed should look like. So, however is most efficient, I’d like to add a second feed to each site that I can access for my full-feed-need purposes. Does that make sense?

I’ve been down several paths, none of them quite appropriate. Hoping someone with more experience can point me towards a solution–I can’t even find a WP function that I feel like achieves my goal (but I”m not a very good dev, so I maybe am just missing something).

Any direction on this is appreciated… Thanks, folks!

-Jeff