Which Cross Sell Mod?

I am confused as to which cross sell module I need. I already spent several hours installing and configuring: Multi Cross Sell but it does not seem to have what I need.

I have a picture frame shop and I need to be able to add on acrylic (plexiglass) and matting if the customer needs it for a frame. (I cannot add it to the existing product via attributes it has to be it's own product). I will have thousands of frames and need the mat and plexiglass add-ons to show on each frame. So after the customer selects their frame, then they can add plexiglass or matting as a separate product.

This is what I am looking for:

1. I want to add two cross sell items to the shopping cart contents page (because these are add ons to the initial product).
2. I need to be able to add this cross sell (one way) to thousands of products so if possible I need to attach it to categories instead of individual ID's which would take me forever! I cannot attach it to a model number as each frame will have a different model number.

Basically I don't need anything that special, just the ability to add two items to all my picture frames. But I don't want these two items to show in any other categories (including their own).

Any ideas please?