The drills for taps are usually not fractional,but numbered-confusing,I know but most hardware stores sell taps as aset with the right size drill.
Also,some people braze or weld a cutoff bolt to the tang,so they dont have to thread the tang.So if you have the ability or have a buddy who does thats an option.and yes its the same size,for instance 6x32 for the tap and die,just consider them like the male and female part.
Hope that helps and dont feel bad-none of us did anything 'till the first time
Robert