The 4AFE has timing marks on both sides of the camshafts. The inner marks (facing the drivers side) are installation marks. That is how you install the cams. In other words, you use the inner marks to install, tighten down the caps. Then you have to use a wrench to rotate the exhaust cam to align the timing marks on the outside of the cams (they face the passengers side.
Rotate the exhaust cam until the outer marks are aligned i.E. The intake cam mark is at 3: 00 and the exhaust is at 9: 00. The mark (looking through the hole in the camshaft belt gear) is at 12: 00.
Then you can install the timing belt. If you align the inner marks and install the belt, you will be about 90 degrees off timing.