The 'star wheel' has the last two digits of the calendar year in it, in this case 73 for 1973.
Inside any ray is one to four dots. Each dot is a week. A part cast the first week of 1973 will have one dot in the first the first ray. 3 for 3rd week, etc. As each week passed, another dot. Each open ray space is a month.
The 09104 is the vendor number for the supplier that made the part for Chrysler - whoever that was.