The condenser doesn't care about voltage, Doc. Some of the ones I've seen that were saved from the 50s and 60s have dried out and no longer work, however. The insides of these were just foil wrapped around a dielectric film or gel. Time is the worst enemy...the stuff gets brittle and then fails to do the job. You might get a good handheld multimeter and check the capacitance. If it isn't at ~.22uF, then don't use that one. Good luck.

~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end