....but here is what the book says:
To check timing chain slack, place a scale next to the timing chain to detect any movement in the chain. Place a torque wrench and socket on the camshaft sprocket attaching bolt. Apply 30 ft lbs{cylinder heads installed} or 15 ft lbs(cylinder heads removed) of force to the bolt and rotate the bolt in the direction of crankshaft rotation to remove all slack from the chain. While applying torque to the camshaft sprocket bolt, the crankshaft should not be allowed to rotate. It maybe necessary to block the crankshaft to prevent rotation. Position the scale overthe edge of a timing chain link and apply an equal amount of torque in the opposite direction. If the movement of the chain exceeds 1/8", replace the chain.
The kit is cheap insurance. I'll change it. Thanks guys
Small Block