They aren't standard pistons to begin with, you won't know whats going on until you remove a piston, measure it and then measure the bore. It does look like too much movement but people often leave a large bore to piston clearance when using forged pistons (can't see what pistons they are from the vid, other than the valve cut outs). Have a measure mate and compare it to fords quoted clearance to see how reasonable (or not) it is.

Also, if the crank looks good then don't have it polished. Polishing increases clearances unnecessarily and can often leave a slightly oval journal.

Rob,