I have an early SS with no date and is notched. According to the Wiki, that should make it a 1948-1949. Is that correct? If the case is not available, is there any way to say for sure it's a '48 or a '49?
Nope. And the date range would actually be 1948-50. Although there were some rare V3 (1950) date coded Super Speeds, full blown date coding didn't begin until 1951 (W).