F40 side grills doubt

in my opinion,not, my f40 are original and there are not this grilles

 

There are two types of grills. Early net and later slot types. I dont know when they did the change.

 

euro car might have them. I know the older euro cars have them when US cars don't

 

Looking at the F40 spare parts catalog (dated March 1991), you can see that there were 2 references for the original side lower grills:
- ref 62990100 and 62990200: RH and LH "slits type"
- ref 63394100 and 63394000: RH and LH "nets type"
So maybe your car has the "nets type" grills. Would then be original.

As an alternative, i had a talk with people at Pozzi (Ferrari France). The guys fitted grills looking abit like yours on the F40 of some of their customers. It was "home-made", and fitted on early cars to protect the side doors as -for the very first cars- the F40 was delivered without grills. But i don't believe you has the "Pozzi grills", as their nets were horizontal/vertical.

Always fun to look into history of these "special" cars