[Palf70Step]

Andy, does this help? I save this off TCI Automotive's website a while back, but can't find their site anymore.
I don't have any, but maybe this will help.


TH400 Speedometer Gears
Drive Gears
7 teeth - red
8 teeth - black
15 teeth - brown or gray*
16 teeth - orange
17 teeth - red
18 teeth - yellow or blue
19 teeth - yellow or white
20 teeth - green
21 teeth - black

Driven Gears
16 teeth - (truck)
17 teeth - (truck)
18 teeth - (truck) code H
19 teeth - (truck) code J
20 teeth - (truck) code K
21 teeth - (truck) code L
22 teeth - (truck) code M
34 teeth - light green
35 teeth - pink
36 teeth - white
37 teeth - red
38 teeth - blue
39 teeth - brown
40 teeth - black
41 teeth - yellow
42 teeth - green
43 teeth - purple
44 teeth - dark gray
45 teeth - light blue

Notes:
Two aluminum housings are available for driven gears with 34 or more teeth. One fits gears from 34 - 39 teeth and the second one fits gears from 40 - 45 teeth.
The driven gear housings go in the case just forward of the tailhousing.

Andy if I figure this right with the calculator they provided, using a 3.07 and 29" tires
you'll need a 8 Drive gear and a 17 driven gear
or a 17/36
or a 18/38

for a 31" tire it will be
8/16
17/34
18/36

Again hope this helps ya and I think my figures are correct.

Oh yeah, I don't know why some of the driven gears mention turcj/code, but no color.