Here's a little trick for you: the cams and covers actually have holes in them that will help you align them to TDC. If you look at the covers, you'll see a hole in each of them about 3/8" in diameter. The cams have corresponding holes that will align with the cover holes when the cams are at TDC - provided that the gears marks "UP" are in fact facing up. If you get two small dowells, you can drop them into these holes and the cams will be locked in place at TDC. Do this to initially place the timing belt on the motor and remove them before you try to turn the assembly. I've found this much easier than trying to eyeball the cams.

hih