if you do not remove/mess with the cam synchronizer unit timing is merely aligning the dots.
it helps, but is not necessary, to set the engine at TDC before you start.
once the timing cover is removed the chain & gears are exposed, and you can see the timing marks.
now you can turn the engine over and align the dots. big gear points down, small gear points up.
then replace the gears/chain and put them back the same way.
the cam will have a tendency to jump around, just rotate it back to where you need it to be.