Bill - What are the port inlet and outlet sizes on your T-fitting? If they are both 1/4", this Classic Parts
Brake Line T-block fitting may be just what you need.
Their description doesn't include 3100 1/2 tons, but the picture looks to match your 2nd one above.
The same item from Jim Carter
MEE247 has a more detailed description of "1947-50 All, 1951-57 3/4, 1, 1 1/2 and 2 ton. Frame rail divider block with retaining nut. This brake line T attaches to right frame rail. Receives master cylinder line and divides it to front and rear wheel cylinders. Includes retaining nut. Is 1/4" inlet and 1/4" outlet. Sold each master cyl line = 7/16"other 2 lines are both 3/8" "
