The first time gm used the blazer name was 1969 on a fullsize. They were a k5. The s-series blazers started in 83 and ended in 94. Since all first gen s-series basicaly used the same tails we will call it 82-94. S-series were called s/t series. The s was 2wd and t was 4x4. Notice your link it says c/k series. In full sizes c was 2wd and the k was 4x4. My 1987 blazer 4x4 is actually a t-10 blazer if you ask gm, my 88 2wd truck is a s-10 (gmc was s/t15). If your look the years it list are fullsize model years. Besides that if you own a first gen just looking at the pics says its not a s-series.

Not busting ya balls its an honest mistake if you don't know.