Solved - NEH 4394: Fiat 1500 Spider by Pedro Serra

[Carnut]

What's this and who built it, for 1 point?:

Remember - solving puzzles using 'Google Search by Image' is BANNED on AutoPuzzles!

[Carnut]

Experts?

[72Must]

What's this and who built it, for 1 point?:

Remember - solving puzzles using 'Google Search by Image' is BANNED on AutoPuzzles!

Fiat 1500 spider by Serra of Spain ?

[Carnut]

Fiat 1500 spider by Serra of Spain ?

Yes it is.
You did very well to track that one down with no questions, as it doesn't even seem to appear on any websites focussing on Serra. 
There is actually a bit of doubt about whether it really is a Fiat at all; there are those who think it's a Pegaso, which may be more likely since no Serra website refers to it.

The un-modified puzzle picture plus front views:

[Carnut]

I can still find very little reference to this car.
The car pictured below is very similar indeed, which doesn't actually prove anything but still leaves a question mark over whether it's a Fiat or not:

[D-type]

Is it possible to blow up the original of the 2nd picture to show the badge on the nose more clearly?

[luisps]

No doubt it's a Fiat 1500 from 1940 (as per the license number reflects) The first Pegaso cars are from 1951 and the Pegaso Spyder Serra from 1956. In front of the dificulties of buy a modern car until the 60's in Spain some people use to rebody their existin cars into a more modern look, in this case that body was made by Serra in 1953 as explain the book of Serra's history.

[Carnut]

Is it possible to blow up the original of the 2nd picture to show the badge on the nose more clearly?

It can be blown up but it will just blur the image so it wouldn't help.

No doubt it's a Fiat 1500 from 1940 (as per the license number reflects) The first Pegaso cars are from 1951 and the Pegaso Spyder Serra from 1956. In front of the dificulties of buy a modern car until the 60's in Spain some people use to rebody their existin cars into a more modern look, in this case that body was made by Serra in 1953 as explain the book of Serra's history.

Thanks for this which probably answers the question anyway.