4.08 Frontier gear swap

T_K

7AT
4.924
3.194
2.043
1.412
1.000
0.862
0.771
3.357 (Final Drive)

6MT
3.794
2.324
1.624
1.271
1.000
0.794
3.692 (Final Drive)

Multiply gears by FD.

7AT
16.530
10.722
6.859
4.740
3.357
2.894
2.588

6MT
14.007
8.580
5.996
4.693
3.692
2.931

6MT (w/ 4.083 FD)
15.491
9.562
6.631
5.189
4.083
3.241

Now look at 7AT vs 6MT w/4.083:
7AT 6MT
16.530 15.491
10.722 9.562
6.859 6.631
4.740 5.189
3.357 4.083
2.894 3.241
2.588

The first 3 gears in a 7AT w/ OEM FD is geared more aggressively than a 6MT even with a 4.083 gear. The top 3 gears favor the 6MT, even without a final drive, the gears are closer. Up to 3rd gear the numerical values favor the 7AT, but the 6MT spans the 4-6 in what the 7AT spans with just 4-5.