Joining two lists of surfaces together, item by item

Hi.

This is my first post here, so apologies if what I am asking is obvious!

I have two lists (same length) containing surfaces. The surfaces are all in contact with each other. I want to join together the surfaces two-at-a-time (those with the same index from the two lists) ending up up with a third list of surfaces with the same number of items as each of the initial lists.

The command brep join only has one input, so I don't see how to manipulate the lists to combine them item by item - how do I do this? 

Thank you!