SG 43 plate 146 current number 163 1871
This lovely scan shows plate number 146 (circled)
and the Perkins current number 163 (above
stamps AA and AB).
Image source British Postal Museum from the R M Phillips Collection. Vol XXVIII Pg 25
Postmasters Circular - explaining the introduction of letters in all four corners
Image source British Postal Museum from the R M Phillips Collection. Vol XXVIII Pg 2