This street car was shipped in 1966. Shelby started with 427's, went to 428's and the BACK to 427's. I often hear there were more 428's than 427's total, but I'm still not convinced that's true. A best guess using some data is as close as you will ever get to the exact numbers of 427 vs 428 engines.
Worth more as a street car? Tough call, I would not assume that to be the case. Lot's of folks (most) prefer the SC look, might be worth more as an SC depending on the buyer.
Woodz, you really had me going with the "snow flakes". My first thought was, "Uh oh, I don't have a clue what snow flakes are, and it sounds like I should know this??!!??" Ya got me good man!