its very easy. Remove the cross in between by clicking out the small circle shape (spring action) lock and then bolt out. Once cross is out you wi figure it out by looks.
1 or 6 cylinder, job will be same opening up whole engine with head too. You mean for changing piston that go in cylinder, as i doubt you can change the cylinder as its hard metal shaped engine block curved 6 cylinder out of it. For changing 1 or 6 you got to change the whole block.