I suppose that I "wised up" before the kool-aid turned fatal. I got diverted into offroad racing. More of a 3-dimensional motorsport.
Anyway, with the thought of this issue, I checked my original 1972 GCR (General Competition Regulations - the rule book that told inspectors what the race cars in Production classes should be built like) with 1973 updates. SCCA used to publish a new rule book whenever there had been enough changes to warrant printing an entire new book, but published pages to insert into older books at regular intervals. And if you were a member of SCCA, you got those updates mailed to you as they were published. I was then (early '70s) an SCCA Tech Inspector. I have my '73 issue as earlier editions had been superseded and I replaced the old with the new as I went along. I kept my rule books bound with the 2-prong sliding clamps so I could update them as I went along. I stopped working SCCA Tech in 1975, so the '73 updates were the latest I had.
The homologation of any car was very rarely altered over the years, and the older the car got, the less likely the factory paid any attention to homologation papers for it. So I'm going to consider the 1972 issue of the page for Corvette 283 to be pretty well representative for Corvettes that came from Chevy with a 283 engine. The page does NOT include any indication of year models included, so I'm going to infer that ALL of the years Corvettes were offered with a 283ci engine are included. That would be 1957-1961.
Under "carburetion" it lists "Rochester fuel-injection (see alternate below)"
At the bottom of the page under "Alternate Specifications" it lists "Alternate carburetion: one or two Carter 4Bbl"
So I conclude that even in the late 1950s, and all the way up to when SCCA created the GT1/2/3/4 classes, anyone of the 3 different optional carburetion setups would have been acceptable all in the same class. 1-4bbl carb, 2-4bbl carb, or Rochester fuel injection would be appropriate. On the engine dyno, the 2x 4bbl might have competed with the fuel injection for max hp. But on the track, the 1 x 4bbl may well have provided the best tractability and widest power band for general purpose use on a road race car. Road racing is not the same as drag racing or super speedway where max hp at high rpm at wide open throttle is what you're after. For road racing, an engine has to work well at low and mid throttle too. That's why in open sports racers big Chrysler Hemis could not keep up with small block Ford and Chevies or even 215ci aluminum Olds engined cars.
Good call though oldtimer. I had to look it up.
Slim, that Vette looks good.
Back in the day, Vettes on tracks with long straights had trouble with the stock windshield folding back from wind pressure. Stingrays had more trouble than C1 Vettes. In fact, I was told as a Tech Inspector to not allow a stock windshield on C1 or C2 Vettes for races at Riverside. So plexiglas windscreens were popular. So I would cut that windscreen down even further. However, I ran across a picture on the net of a late C1 Vette SCCA road racer with a windscreen very much like yours. So go for it the way it is.
Seat belts should be 4-point with 3" lap belts and 2" shoulder belts with lever latches and leather pads behind the latches.
Rules stated that bumpers may be removed, but not grilles. I like early Vettes without the grille, but that was a no-no.
Here's a picture of Doug Hooper's Vette racing in SoCal.
Wiper arms could be removed, but the wiper mechanism had to remain and be workable. So the shafts should stick out of the cowl. .020" /0.5mm craft wire would work for those.
Headlight glass may be removed or must be criss-cross taped to keep the glass from scattering on the track in a crash.