I got my K&J Magnets in and two D88-N52's work the best when sticking them on the horseshoe magnet. These are 18.08 lbs pull force and provide ~1.3 volts A/C under load with the light. If I unscrew the light voltage jumps up a bit over 2v A/C. I haven't even tried disassembling the magnet, which I'll leave to my bother to try with the BX088-N52 magnets.
I also got my parts box from Jensen. The boiler gaskets were more or less not very useful. I had to modify the ones for sight tank, as the center hole was too small. Then the steam line to the engine gasket for the tank either wasn't included or none would fit - so I had to revert to making a new one out of paper. I suppose at least the ones for the whistle and pressure popup valve worked.