Fascinating and fast progress, I do like your frame.
Have you decided on a chassis yet? Might be an idea to have a rolling chassis to line everything up to before fixing the panels in place.
Also, I'm not sure if this is the change you're making, but the 356 and 356A have a bit of a beak in the centre of the front end rather than going straight across. You can see it in this pic -
The 356B and C models had a smooth curve, but the headlights are much higher up in the wings (I always thought that the Nissan Micra K12 front end would be a good starting point for a later model 356) -
Images sourced here:
https://www.youtube.com/watch?v=82NNlFTbwbs
https://en.wikipedia.org/wiki/Nissan_Micra
Anyway, I'm sure it's going to look stunning whatever direction you take!