the proper way is to degree the cam in with the new timing chain..

but being an oem cam do would you really know the cam timing and the centerline needed...

i would buy a good double roller timing chain...and just replace the chain and sprockets.

you would not have to remove the keyway to change the timing chain...

be aware there are two bolts that go up from the front of the oil pan into the timing chain cover...also replace the seal in the timing chain cover..and front seal on the pan...