No, you check it with the tensioner installed. If the rails are all new, and the pins won't insert at 45°, either the chain is stretched or the cams weren't adjusted properly in the first place. The FSM procedure is at this link.

You'd remove the tensioner if you were to actually adjust the cam timing, per the procedure above (it's step #4). If you attempt this, remember that the twelve Torx stretch bolts for the cam sprockets & two stretch bolts for cam adjusters (14 total) must all be replaced, to the tune of ~$50 or so.