Bill is right on the money with his reply.
Also, even if the scales were accurate you're talking about a barely perceptible diff between the two scales to anyone but a very nictpicky viewer.
Using an online reference for the 2nd gen Hemi that had it at 30" in 1:1, then plugged that into a scale converter the scale diff is only 1.27 mm, or 0.05".
I personally use the eyeball test. If it looks right, I use it.
Personally, I'm a traditional Chevy man, but I back using something other than a Chevy IMHO. 😊