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.002" was the max piston clearance recommended by Ford when new, with todays pistons and the roads and speeds we drive on, that is not enough, they
will stick in the bores, and scar the block and pistons. I recommend a minimum of .0035" piston to wall clearance. I do more than that on my performance pistons. However, this should not cause tightness when cold, just ruin things when they get hot.
When you fit the bearings, were the caps on correctly? .002" clearance should be plenty, and about right IMO. Also the babbitt can be too tight in the radius, and/or the side clearance.
With .0025 - .003" clearance on the mains you should be able to spin the crank by hand, fairly easily. Also everything should be generously oiled when assembling.