I did a complete teardown and had heads rebuilt. I kept all my parts in order, I though. I was sure about 1 and 3 piston. I wasn't sure about 2 and 4. Might have switched them up. Kept the piston and matching wrist pin together. Kept the connecting rods on order on the crank. My confusion is on the AB markings on the case. I have 1 A and 3 B pistons. The block says the A is #1 but I had it in the #2 spot. Also there are 2 L and 2 R pistons. I have on of each on each side if the engine. The manual says the little dot faces the front of the engine. It appears both L would have to go on side and both R on the other. Does it really matter which one goes where?

The dots face forward. Place the pistons accordingly. The A piston should go in the A cylinder.

 

O.

So will both the L pistons be on the drivers side and both the R pistons will be on the passenger side? I know I am overthinking this but, I am sure that isn't how it was before. 

Don't remember my 07 pistons being marked L and R.

Once the rings are attached per fsm, the A piston has to go into the A bore regardless of any conflicting L/R as a B would leave too much gap in an A bore.

 

O.

The FSM shows only the U5 (CA emissions) pistons are marked L and R.