Here's a much better how-to:
http://www.ttzd.com/tech/timingbelttech.html
To get the belt lined up, first try to get the notches on the crank sprockets lined up with the marks on the rear timing covers. Some of the gears (I think driver's side ones) will want to rotate when you turn them because of the pressure from the valve springs. Once they are relatively close, and you line up the punch mark on the crank sprocket with the notch on the oil pump housing, try putting the belt on. The only important part is to have the notches on the cam sprockets lined up with the lines on the timing belt. The marks on the rear timing covers are just for reference.
As for rotating the engine manually for the tensioner, follow the FSM procedure exactly like it says. Once you set the tensioner and rotate the engine a few times, you have to keep checking the gap with a ruler or feeler gauge. If the gap is too wide, take the whole tensioner off, put it in a vice, close it some and put the stopper bolt in and try again.
For cam seals, remove the cam sprockets and use a pick or something similar to remove the old ones. Then use a socket or piece of PVC pipe and tape the new seal in with a hammer/mallet. You can use the old seal as a buffer when doing this. Also remember to lube the new seals up good with oil.
Is there a reason you want to remove the cams themselves though?