225 popping out the exhaust, but...

Cool!

I mentioned the metal case and heat sinking as I would expect that this capacitor will probably get some heat in it. A low loss (low internal resistance) type would be needed since there is some current being pushed around here so some heat will end up in the capacitor even with and low ESR type. I would expect for the 40's-50's era, a paper dielectric type would be used; I am not sure mylar dielectric types existed in the 50's; they did in the 60's.

It would be tempting to get a high quality modern capacitor of the right capacitance value to get around the newer variable quality stuff, but I have to wonder how it would handle the heat.