Scott #s - The 3792 is the second stamp from the left in the scan below.
3792                  (25c) Eagle – gray background & gold eagle
3793                  (25c) Eagle – gold background & red eagle
3794                  (25c) Eagle – dull blue background & gold eagle
3795                  (25c) Eagle – gold background & Prussian blue eagle
3796 (Stamp with plate #) (25c) Eagle – green background & gold eagle
3797                  (25c) Eagle – gold background & gray eagle
3798                  (25c) Eagle – Prussian blue background & gold eagle
3799                  (25c) Eagle – gold background & dull blue eagle
3800                  (25c) Eagle – red background & gold eagle
3801                  (25c) Eagle – gold background & green eagle
3801a                Strip of 10, #3792-3801
                Plate # strip of 11, 2 #3801, 1 each #3792-3800
                Plate # strip of 21, 3 #3796, 2 each #3792-3795, 3797-3801   

Note: 3796 exists with and without a plate number.   

 
AmerEagle11.jpg (184072 bytes)
This view shows a plate number strip of eleven.  The vertical bar, which repeats every 20 stamps, can be seen on the reverse of the first stamp on the left.  The back number is on the same stamp as the plate number.  The actual stamp colors are more vivid than what I can get from my scanner.
 
AmerEagleB.jpg (30140 bytes)
This view shows the vertical bar in relation to the plate numbered stamp which is located on the reverse of the black back number.