Ok, you win, the front axle is not fixed to the frame, but has a center pivot on JD & NH utility tractors
Looked up the exploded parts view of the JD 3005
compact utility tractor on the JD website.
This tractor is about as close to the N series as anything on the market, accept for maybe the NH 1500 compact tractor.
The 4WD model has the center pivot housing integal with the differential housing. Appears to be a very heavy duty casting.
The 2WD model has a front axle with a center pivot with a configuration of very similar geometry to the N series, except it is a weldment rather than a casting.
Also looked up the exploded parts view of the NH 1500 compact tractor
The 2WD & 4WD models both have a front axle center support. The 4WD model pivot has zero offset to the front axle. Again the 2WD model front axle geometry is similar to the N series
It is a weldment rather than a casting.