How to override extruder 2 print area reduction?

[Rocket 1]

I have a model that *just* fits in the build area when I don't generate support but the build area is reduced by a couple of millimetres when generate support is checked.  The model only actually needs support in a small area in the centre of the printer so technically it is printable but I can't get the model to fit to allow cura to slice it to see that it does fit....

 

As an aside, this is a model I used to print in previous Cura - is the area reduction a new feature of 3.6?

 

Back to the important question, please could someone explain the best way to convince Cura to slice this model?

 

Thank you!