On our 6th Gen Ipod-A1238-80GB tabs are located as follows:

(all tabs are about 1/8 inch in width)

The sides tabs as measured from bottom of Ipod to top,

(1) begins at 5/8" - ends 3/4"

(2) begins at 1 7/16" - ends 1 9/16"

(3) begins at 2 7/16" - ends 2 9/16"

(4) begins at 3 1/2" - ends 3 5/8"

Top tab measured from left,

(1) begins at 1 3/8" - ends 1 1/2"

Bottom measured from right,

(1) begins 3/8" - ends 1/2"

(2) begins 2" - ends 2 1/8"

From previous comments,use the aluminum can trick or thin tools as in referenced video to unlock clips.