rotating assembly

i got a 3.4 engine from the salvage yard and it looks great almost like sumbody had recently rebuilt it.underside of piston still is grey very lite oil stanage and the inside of the heads where the same way with new valvetrain,the piston walls look shiny and clean as well. Its a sfi and i have a 2.8 tbi so im doing the swap..i have it broke all the way down to the rotating assembly..i can turn the flywheel and rotate the pistons with one hand easily all the way around..Now im wondering is this to loose and i need to replace the rings or is that normal and proceed with my build? Dnt wanna b mad when i have it all 2getha and find out i should have did it?