I Need help! Rods or piston mix up! NEED HELP!!

Pistons usually have a notch or something to indicate the front of the engine...also, assuming they were assembled correctly, the notches in the rod that keep the bearing from spinning should point outwards..
As far as what cylinder they go in, if you didnt mark them when you dissassembled, your probably screwed there...
you'll have to try them 2 at a time on the crank and make sure you have the proper side clearances