Based on what I've read here, I'm about to spend $16 plus shipping for 2# of TSP. Is there any downside to this method.
For rusted side rods and valve gear, I've used the soak in vinegar followed by wire brush method recommended by someone on this forum a few months ago, with good results. Except that the eccentric cranks need to be blackened now.
As for re-tarnishing, I shined up a dozen copper journal boxes and some brass parts several months ago and they're still bright.