In my GTN pack I have the list of all 11 GTN's and who the supplying dealer was along with chassis numbers etc.

The letter from then factory to each owner lists the car like so:

MORGAN AERO 8 GTN / CUP SPORT REPLICA

the 11 chassis numbers are:

G0273 RHD #1
G0274 RHD #2
G0275 LHD #3
G0276 RHD #4
G0277 LHD #5
G0278 LHD #6
G0284 LHD #7
G0285 LHD #8
G0289 RHD #10
G0291 Unknown #9
G0292 RHD #11

So, definitely 5 RHD and 5 LHD versions. Not sure about #9 as it didn't go via a dealer and wasn't Eric's car.

Aero 8 GTN. #10