Congrats again Bob, I knew you could do it!!! When that check engine light went out, didn't you have a real positive feeling of accomplishment ? So the fire box is different from the older models. The vacuum line coming from the top of the fire box goes where? Sounds like a large vacuum has formed in the engine block. That should stop any smoking. It should also produce more power. It's like a turbo in reverse.
We will all have your post to look to when we turn the oldies into the retirement heap.
I glad you had a good experience fixing the fire box.
Good Luck!!! RK