Sorry, my mistake!
The descriptions of the job made me think you were doing the rears!
The fronts are quite doable. I did mine with an offset O2 socket from memory, with a couple of socket extensions.
Definately fiddly, but I got to both from above. I think I only removed the engine cover and inlet pipe.
I thought Bosch had stopped making the sensor with the correct plug, for a sensor with a generic plug and a new plug for the harness (seriously, Bosch?).
Michaela would be replacing these quite often, so she should know.
I ended up with NTK sensors on mine.