Instruction changing timing belt 1979 Alfa Romeo Spider Veloz?

With Cam Caps loosened, FIRST loosen timing chain tensioner, press it in to loosen tension, Crank using ratchet to TDC (Top Dead Center on crank pully, (to keep from damage to pistons), align Exhaust Cam Timing Mark to mark on #1 Exhaust cam cover, then take up slack between Exhaust & Intake Cams (on top between the cams), Then align the Intake Cam to mark on #1 Cam Cap, "Now" loosen the 17mm bolt to tighten timing chain, rotate engine using rachet two times, reset TDC at the crank, and look at "Cam Timing Marks on both the Exhaust, and Intake Cams. If you did all this correctly the "Timing Marks" should be lined up so TDC,Exhaust, and Intake marks are all the same.