From what I could find, the punch card machine allows to create a second build for the same character by redistributing and saving a new set of SPECIAL attributes and assign new perks. This means (again, to my understanding), that I can have, for example, a heavy gunner build and a shotgun build that I can switch between.
However, when I was leveling my basic shotgun build, I didn't choose any heavy guns related perks, as both shotgun and heavy guns use Strength as their main SPECIAL attribute. Hence now, I cannot simply switch from shotgun to HG, because while I've unlocked the Shotgunner (regular, expert and master) and the scattershot perks, I don't have any cards for the heavy guns (heavy gunner/ expert HG/ master HG /Bear Arms).
If I use the punch card machine, will I be able to re-select perks as I was leveling from lev 1 again, or does it only allow to select already unlocked perks?