My 77 t-top has the fairings & ground effects that are common. But I noticed looking @ other mid - late C3's that most do not have the spoiler molded into the rear facia & or the taillights are inset independently, while both on each side are molded inset together. Is this an RPO with the build or what. If so, does anyone no the code, or the model it relates to. IE. - L48 or L82 style. I'm lost on this one....Help anyone !!   VIN # is 1Z37L7S4443289

Ken, I have the same aftermarket fiberglass rear bumper on my Vette that you do.  Many people replace the cracked original bumpers with fiberglass ones which are not like the original equipment.  The previous owner of mine put it on and, as I liked it, that is one of the reasons I bought the car.  I really like the spoiler effect rather than the slope of the stock rear bumper.  I like my car to have a distinctly different look from everyone elses.  Enjoy your C3 and make it yours.

Yup...definitely aftermarket...but they do look good!
 To find your build date, look on the door. There should be a tag there that gives you the month/year. If the tag is missing, just look farther forward. On the driver side, when you open the door, you'll see a small, metal tag riveted to the body, in the headlight switch area of the dash. It is on the outside of the body there...not inside the car. I prolly got pics somewhere.
Anyway, once you find the trim tag, as it is called, write down the numbers, and then come here, and hover your cursor(mouse) over the "Research" tab at the top of the page. When the drop down menu appears, click on the "C3 Corvette Build Dates", and you can de-code your date from the list there. There is also a pic of a trim tag there, to give you an idea of what to look for.