I will try to dig up the old thread where there were some spy shots of some unknown small BMW sedan that it was speculated could be a 2GC. It would be interesting to compare. Edit: found the old article – it was not on BimmerPost. Looking at the pics, they appear to be the 1 Series sedan, not an early test mule for this 2 Series Gran Coupe.
40i/M40i = CLAR (RWD/AWD), longitudinal B58 I6, 322hp+
M35i = UKL (AWD), transverse B48 I4, ~300hp+