Now that you have that problem solved Tim, you can set your future thoughts on the heat exchanger on the back. They have a tendency to rot out, seeing they're made out of sheetmetal. I had to weld in some patches when I 1st got the stove, and I'm sure they should hold up for a while. But down the road, it would be nice to have a back-up. Now that I think of it, the stove I parted out, that you got should have one. If it's rusty, maybe you can have it professionally patched, for a future replacement. I know the furniture Co. in Pa (?) who sells Surdiac parts, also sells replacement heat exchangers. But they don't look anything like the original, (very boxy), and cost an arm and a leg.
But for now, enjoy what you've got.