Given the new and bulky shape of the window well the excavation needs to be extra large to accommodate the install brackets. This is strange because the old style window well was huge already. The code changed and now the old precast won't do for fire escape.
We dug out just enough and they all fit. What a relief. Less luck with the stairs however because one was too large and will need modification.
the precast window well is definitely not the fire escape bottleneck