Smallblock seat height was 1.88 Big block was 1.91. Which still doesn't solve your dilemma, because it's less than the BB. Did you happen to notice any slop before you pulled it apart? I ask because you never know what someone did before, like shorter pushrods etc.
Here is what I am looking at.
http://www.compcams.com/Products/CC-'Hydraulic Lifters'-0.aspx