In case of Corolla gaining access to the whole dashboard is a completely different story as compared to other cars. The beige strip spanning the whole length of the dashboard and the glove box once removed provide access to the dashboard's inside. And removing them requires simply pulling out these parts. There are no nuts and bolts. Once the tracker is installed in place, the same pieces are pushed back in and snap into place.
My suggestion to you is to be there when the tracker is installed and remind the person installing two or three times before to take extra care and that you would not be responsible if even a single clip is broken while detaching and attaching the above mentioned parts. Check the car thoroughly once everything is back into place, including the headlights, fog lights, back lights, indicators, fitting, head-unit, wipers, etc.
There are other places too where a tracker maybe installed. The choice of location would depend on the person installing the tracker or the place specified to him by the company of insurance.