Okay, here goes. This is about the best side on shot I can get at the moment, and yes, it is doing a Peter Pan in Panto impression -
Close up of the back end shows that there's quite a bit of height above the rear arches -
23cm from the arch to the 'shoulder' of the rear wing -
And 40cm from the arch to the highest part of the deck -
The highest part of the rear deck is about one metre across. Bear in mind that this is a stretched body, a Banham New Speedster, I suspect, that's going to need about 180mm taking out of the wheelbase. That means the gap between the rear of the door and front of the arch will be about 75mm less once I've taken the angle grinder to it...
Hope that helps.