Put a drop or two of Loc-tite on each fastener. (...just a drop or two, --not saturated!) Then tighten each bolt finger tight, ( the pressure plate will not be seated against the flywheel) and then use a socket & ratchet to turn each bolt one half turn doing this operation in a complete circle until all bolts are snugged and the PP is seated against the flywheel. Then tighten one-half turn after they are seated and it should be tight enough.
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