Looks to me like the damper broke off! I can see the rubber insert still present. I'm betting you will find the pulley bolted to the hub like all the modern stuff is, and there is probably still the bolt present that holds the damper onto the crank.

Just for kicks, I opened my 54 Dodge truck factory service manual. For the 241 V8, under removal & installation of chain case oil seal,

on step 3, it tells you to remove the radiator and remove the crankshaft pulley retaining bolt and flat washer.
Step 4, Install tool # C-3033, pull the pulley off the end of the crankshaft and remove the key.
Under installation,
Step 5, Place the crankshaft pulley and damper hub key in the slot and install the pulley assembly and flat washer. Attach tool # c-3033 and press assembly on the crankshaft. Remove tool and install the hub retaining bolt. Tighten to 125 foot-pounds torque.

Under Installation of Vibration Damper, Figure 81 shows a picture of a dust ring, the hub, the damper, the pulley, lock washers & bolts, and a damper retaining washer & bolt. An interesting note here, the Vibration Damper install is under engine rebuild. Here it tells you to torque the retaining bolt to 135 foot-pounds where with the seal replacement it tells you to torque to 125 foot-pounds!

Then basic engine timing.
step 1, Rotate the crankshaft until number 1 cylinder is at top dead center (or firing position). When in this position, the pointer on the chain case cover should be over "DC" on the vibration damper.

This reaffirms my thoughts that your damper is broken! Gene