My next dilemma is how to shape the rear lip. If I keep it horizontal the gap will be quite large at the rear. If I go for minimum gap it must be bent quite sharply and create a "gutter" along the lower edge. Can you say "rust trap"?
I'd like to know how they were originally. The best picture I could find is from Gordon Raymond in Pathung's excellent thread. Let's see if I can steal the link:
This should be a link to the place where I stole it from:
'63 Giulia Spider Normale Restoration (Euro)
It seems from this that space is left for the lip to slope down slightly. Can someone with an unrestored car tell me how it was originally?