bought a few 16 volt caps

[Psycho Bass Guy]

You don't really need to worry too much about the speakers as long as the cab is sealed. It's still technically possible to blow them from too much bottom, but until you start throwing potentially more than twice their rated power at them, they should be alright. Back in the late 60's, ported cabs were juts getting into widespread PA and instrument use. I'd imagine the raw sound of an EB pickup could hang an Acoustic folded horn quite easily.