I've been following this thread with interest and it seems to be well in hand.
I haven't commented because for almost all brass repairs I do, I am using my resistance soldering station...which is an expensive item to purchase unless you're planning on doing a lot of brass repair or building brass/NS models in your future...and the fix for this problem can pretty easily be done with an iron of sufficient temperature.
However, if a modeler has a lot of brass engines, and keeps an eye on the market for good deal for ones that may be in disrepair or are broken, a good resistance soldering station is invaluable. This is mainly because it facilitates applying highly concentrated heat very quickly to areas where using an iron would de-solder neighboring joints, or damage integral insulation, such as on a set of drivers.
In the long run, spending around $600 for a resistance soldering station with accessories that's 200 or so watts is around the same price as an N-scale modeler might pay for a single brass engine...so, maybe when looked at that way, it really isn't a price that's out of the question, especially since there are repairs and modifications that simply can't be done using any other soldering tool.
Cheerio!
Bob Gilmore