Rex et al:
I am indeed challenged by space and yes, I have just .125" between that rear bulkhead and my garage door. A continuation of the tail is planned but probably not before the car is sorted. I should mention that once the body is built, that rear bulkhead is removed and replaced with a tube structure leaving air in for induction, a place to escape. I remember a number of Trans Am cars decades ago, wrestling with this same problem; what to do about the back of the car? I think they may have been a rule governing overall length and no room to treat this part of the car properly. Through wind tunnel testing, they found that chopping the back off flush was the best compromise. For now, this and maybe a couple rows of vortex generators will have to do.
On the subject of space; I am so restricted, even my trailer length is way too short. I made the car in two pieces so I can transport it on a short trailer. Some assembly will be nessisary but batteries will be included.
John