Stretches for thoracic spine?

I have done PT for my low back/SI joints a few times and have those stretches down. I have started having thoracic spine stiffness/pain. My rheumatologist showed me ONE stretch to do. That's it. Told me to just Google a few.

I will be doing this but wanted to see what everyone else does/likes?

Like for me, I know there are certian stretches/exercises make my low back flare up, not help. And example is bench press, can't do it with out massive spasms. Various types of alternate push-ups do the same. Laying down on my back flat too long for various stretches does that too.

So, with those examples in mind, what do you all do for T-spine and what do you not do? Just want ideas on what to do and what to be cautious of when I try them.