It is indeed a ind numbing process to solder brass with an iron. That's a task that cries out for a resistance solderer. Yes, they can be expensive, but after you pay for them with what you saved by building your own turnouts, you will have it for these kind of jobs, and brass kits. too.
In my opinion No, brass is not Dead. Hallmark’s N Scale SD50/60’s out of the box and added details. Photo 1 & 2 new right out of the box. Photo 3 Original Horn Location. Photos 4 & 5 Horns Relocated over Cab and Long Hood. Photos 6, 7 & 8 added details. Photo 9 Close coupling with True-Scale couplers. Photo 10 a GE Dash 8-40C with more pictures to follow. I use resistance soldering system on all brass models. Pencils or irons will and can damage other parts, Adhesives only where no moving parts are, Bell, grab Iron etc. Enjoy the Pictures.