Oh Geoff, soldering steel is easy. Nice big 80 watt iron. Bakers fluid. Plumber's lead/tin solder. Nice hot iron - and it flows like it was on brass. Admittedly the steel then rusts within minutes, but the joint will be good. Scub in the sink to remove any remaining flux (when nobody is watching), dry and then dunk in Jenolite for half an hour and its ready for painting. Halfords self-etching grey primer probably sticks better than it does to brass.
Next time you are here we can try a few bits and see if I can convince you.