Show related posts using SuperBoxSelect (or alternative) and Articles

Hello

I'm building a blog site that has a main blog trunk which will also have separate blog branches. The branch posts need to be related to the main blog so I'm using SuperBoxSelect as a TV on them where the user can say which of the trunk blog posts their article is related to. Now the bit I'm stuck on is how to take that TV output and then display the related articles alongside the trunk blog post that they relate to.

It feels like it should be fairly simple – If this branch post has this main post ID in the TV then show it on the page, but I just can't get my head around how to do it. I've been trying to think how to reverse engineer the relatedProducts tutorial but, being a novice with PHP, I've not got very far.

Any ideas or suggestions would be most welcome.

Thanks