Cam & Sprocket Installation

According to the manual you have to index your cam sprockets on Cylinder 2-4, take the sprocket of these cams, index them in 45 degree markings. Mount the sprockets again. When the rear cams are installed, indicators on the cam are upwards, sprockets indicators level with the cylinder head, crank at T1-3. You have to turn the engine clockwise(Sabre/Magna) or counterclockwise (Interceptor) 90 degrees to T2-4. Now install the 2-4 cams with the cam indicators facing forward 45 degrees, your newly made index lines leveling the valve-cover mating surface. But really there's no need to it after I found out indexing them and rotating the engine.

All 4 Cams, meaning front and rears go in on T1-3. Make sure the indication markings (stamped in the cams) on the cams face upward and the indicator line on the sprockets original markings are level with the valve cover mating surface. Rotate the crank manually by 2 turns and, if done right, there is no interference with the valves.

Actually this does make sense. If the crank timing is at T1-3, another 90 degrees clockwise(Sabre/Magna) or counterclockwise (Interceptor) on the crank pistons in cyl 2-4 are at TDC. Camshaft markings are identical so the cams should be out 45 degrees at T2-4 from its original position facing 45 degrees forward. The cams revolve at halve the speed of the crank. That's why they suggested to make new index lines putting cams in at T2-4. But why? If you install all cams at T1-3 on the crank all cam timings should come out right.