Harmonic balancer??
OK, just measure the damper diameter and get the tape that is closest in diameter. The motor won't know what was listed on the packaging LOL
BTW, we did the added timing marker on the driver's side because the water pump inlet was reversed from the old 273 and it blocked ANY possible view of the original 273 timing cover marks. So when you are in the garage next, put the water pump in place and see what you have with that before getting further down the road.