Hi Tim & welcome to the club, that's a sweet looking car you've got there
. Is it going to be a strip only car or are you gonna put it back on the street?? By far the easiest way of fitting a grille is to put the SS standard grille back on. It's just a matter of screwing it in place. The headlight bezels screw on seperately. The RS grille is a lot more complex in as much as from the factory they were vacuum operated, which entailed a shed load of pipes, mechanisms etc. It's possible to buy all of the parts to fit the RS grille as per the factory from the likes of NPD in the US. You can now also buy electric motors from Detroit Speed Equipment in the US that replaces all of the vacuum assembly & whilst costly, this is probably the better approach.
Unfortunately the VIN doesn't give any options other than paint & trim details, so unless the car comes with an original build sheet from the factory, there's no way in knowing what it was originally. As it's been converted to a race car, I guess that a lot of the original equipment is long gone. I'd treat it for what it is & drive the wheels off it, it's not as if you're gonna restore it back to stock
. At the end of the day, so long as it makes you smile everytime you get in it, then it's doing its job
What are your plans for it in the future?? By the way, we love photos here
, cheers.....Nige