Ive put Turbulence in the old Robochallenge arena with Ed a few times when that had a one metre square (ish) door, it was awkward. And Turbulence isnt the biggest of machines. (800mm wide x 1000mm long)

How do you plan to arm up the robots? Put one robot in, arm it up, drive it away, put the 2nd in, arm it up, drive it away etc? Or are you having two doors?

Would it be that hard to make it abit bigger?

The biggest a robot can be according to the rules is 1.4metre square. (if i remeber correctly?) So atleast make it big enough to fit that + the arms of the people putting the robot in.

I pressume you have designed the arena in some sort of CAD. Willing to show us all a preview?

My 2p