Posted By:
Richard"So to me, it seems likely that the most difficult back of a T206 Cobb is the red portrait Sov 460."
No, Frank.
The red portrait Cobb Sovereign 460 may be rarer than a "Ty Cobb" back, but all of these are rarer than a Sovereign 460:
BROAD LEAF 460
DRUM
BROWN LENOX
UZIT
RED HINDU
VICTORY
RED CROSS