Piston Slap Tech Question

Ok, so after spending 3 nights underneath my Jeep going over and over each piece, I have a tech question about piston slap.

When I rotate the engine so each piston is at BDC, I noticed that I could make the piston "slap" or slightly tap back and forth in cylinders 1,2, & 5.

Pistons 3, 4, and 6 were tight in their bores, and would not rock or tap...

So my tech question to all the engine builders/techs is this: would this be the cause of piston slap if I can make this happen with just my fingers in the bore from the bottom??

Thanks for all the help; I have been taking pictures and have posted my video of the saga on youtube, and will definitely be doing a full write-up once I figure this out for the masses as this appears to be a big problem with the 4.0's.

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To clarify, I can push up on each skirt with my thumb on each side and rock the listed pistons and make some noise. 3,4, & 6 would not do this...

Anybody know for sure if this is bad?

4.0L's are notorious for piston slap noise. The real issue is the compression. As long as the compression is fine, I wouldn't worry about the noise.