torque converter trouble

okay im putting a ******* performance c4 behind a 351w, when its all bolted up the torque converter has no end play, i can feel play rotation wise so its not bound up it just doesnt slide in/ out. i can feel all three stages of the converter engageing so im sure its bottomed. while its all the way in i can feel about 1/2" to 1" of the snout still outside the trans, is that normal? I have about 1" from the bell housing to the pads on the converter.I have read all kinds of stuff and checked all my parts and i cant figure out whats going on.
anyone know the length the snout should be?
the parts are as follows:

79' 351w
case fill c4
big bell housing rf-d7bp-7976-aa
164t flexplate measure depth 1/2"

any ideas would be great