Clutch & Throw out bearing issue

[DangerDan]

1971 C 10 came with 250 (6) cyl and Three speed
Changed to 327 High dome clutch and Muncie (4) speed
Issue is the long throw out bearing is too long and the Throw out bearing supplied with the clutch does not reach the fingers on the high dome clutch whne I depress the clutch pedal!
We have a very good clutch and drive line house here in Fort Wayne (Where i bought the clutch) that insist if the bell housing and clutch fork are stock the short bearing is correct. I don't seem to have enough throw to engage the clutch.
Is there an intermediate bearing length , (clutch house says NO) or do I need a different fork?
HELP! I don't want to pull this transmission a third time!