Welcome to the madhouse Muelhth1, great choice of car.
Let's assume that your car runs at it's normal operating temperature and that you have the heater turned off!
With the two exhausts running down each side of the cabin and the engine/gearbox through the middle, it is a bit like sitting in an oven isn't it?
Adding additional heat insulation would be a great help on the bulkhead and the transmission tunnel both inside and outside if possible. There are some great self adhesive products available. I have also wondered about adding bonnet extensions to the rear bonnet catches on an Aero. If you haven't seen these, they hold the rear lower corner of the bonnet open. This allows for a better flow of hot air out of the bonnet, but I have no personal experience of these on my car.
I am sure someone better qualified than me will be along soon to offer some more help.
