Nice writeup on opening your old torque wrench.

Is it right that the upper nut in the handle was held in place by the
plastic molding of the handle? So there is less chance of it rotating
out of place than the lower nut?

Also, didn't exactly see where the detent feels come from. I guess
from the plastic lock ring area?

The Lowe's Kobalt torque wrenches are also made by Danaher, but do
carry a lifetime warranty.