After that 2d step, I will surely invest in a set of Brusden-Whites
or in one or 2 volumes to begin.
Which volumes would you suggest to acquire first ?
Get what you can - I have the single loose leaf volume

I have hundreds of old GB stamps : it will be my next country to sort
out ... in 10 years ? When I have finished to classify my KGV's
from OZ :-)
Hundreds? There are about 3000 separately identifiable Penny Blacks!
G