Whoa wingform, I didn't check to see if you had started or not. Yes, you are too dark right now. The closest thing commercially I've found to Petty Blue as it mostly appeared is Tamiya Light Blue. You could still use that here by very lightly shooting some Tamiya white or gray primer there after lightly sanding. This will of course give you the chance to remove some more of your sanding marks. Really, for early Petty cars the old Testors light blue enamel did a fair job, but my photographic references from the book, "Cars of the King" by Tim Bongard and Bill Coulter do show the more bright electric blue on the mid season versions of this car which is what you are going for here with the side chrome removed. This is what the Tamiya color matches. For this version, your wheels should be dark blue too, not too much darker than the color the car is now. So, just do a good bit of fine sanding, prime and use the Tamiya light blue. You'll also find it very forgiving, glossy and easy to use. May even be acceptable without polishing. But, You'll need two cans to achieve full coverage too, because.......
The chassis, firewall, inner fenders, radiator bulkhead etc. should all be the same color blue, with the suppensions black or semi gloss black. You are fine on the interior I think. The floor boards could have been blue too, but the black was ok for some cars as long as the cage was petty blue.
The hood Horsepower decals are both correct, changed race to race. If you want a Daytona type car, go with the 405's. Frankly it was all a joke, the factory HP rating was 425 which was also a fallacy, close to 600 was about accurate.
Your engine looks ok, The Hemi orange, regardless what people may tell you is fine, that was as they were, sayeth the King himself.
So, you're doing fine. The color faux pas on the body actually gives you a better base now for your paint job and will help fill in the scratch marks.
One last thing for now. The Tamiya paint is laquer, generally verboten over enamel if that's what you have already sprayed. However, if you sand it and lay down your laquer primer in very light coats over it (sneak up on it so to speak) and then spray the color coat you should not get any crazing or lifting of the paint underneath. Tamiya is apparently a very cool, not hot laquer, I've done this several times with never a problem.
Dave B.