Gallery with Custom Thumbs

Hello,
I am looking for a way to have a gallery on my post, but with custom thumbs. I am open to any way to achieve this. Basically, I need a slideshow gallery, but don’t want my thumbs automatically created for me…I want to enter my own thumbs that will look different than the large image.

What I am looking to do is create a slideshow that uses boxes or small images to navigate between images…similar to what homepage sliders often do.

I would appreciate any help!
Thanks!