FSD stack is being tested in Europe as a regular Autopilot, it is intended to just replace the old stack and keep the same functionality; the work is still in early stages and will take some time
radar in S/X isn't used now and it will be needed to homologate FSD in other markets
Model 3, Model Y and Highland will probably not get radar
the front bumper camera will appear in other models when Cybertruck launches or a little bit before that
the front bumper camera will be connected with the same harness as the front headlights and other front equipment (mentioned in one of the following comments)
Having a front bumper camera may soften the blow of not having the ultrasonic sensors.
Hell, I wish I could have it retrofitted to mine, which has USS
This was posted by the guy behind the Tesla Android Project (https://teslaandroid.com/).
In summary: