I got everything apart. I figured out the chainstay bridge had to come out and then it was relatively easy to plug the tubes into the new bb. The DT/ST didn't want to separate because there was an internal fillet, so I inserted a big bar in the DT in preparation for heating and it just popped loose. I'm taking the old rear triangle the rest of the way off next, I just wanted to see how hard it was to get to this point.
I didn't exactly work too hard to preserve the chain stays because they are going to end up as part of a wheel dishing tool or something like that.