There was more than one radiator for the 73 Challenger.
Here is a list of numbers:
Mopar Radiator Guide & Specifications 1962 to 1974
Mopar Radiator Guide & Specifications 1962 to 1974
Part # Year Body Size Engines Trans HVAC Notes
2099894 1962 B 22" 318 Both HI ALT-A/C
2099896 1962 B 22" 318 Both Heater
2099898 1962 B 22" 361 Auto Heater
2099899 1962 B 22" 361 Both All
2099901 1962 B 22" 361 383 413 Both Heater
2099901 1962 B 22" Both Max Wedge
2099902 1962 B 22" 361 383 413 Both HI ALT
2099903 1962 B 22" 361 383 413 Both A/C
2099905 1962 C 22" Both Heater 300H
2099907 1962 CD 22" Both HI ALT-A/C C3, Y1
2099908 1962 CD 22" Both Heater C3, Y1
2099917 1962 C 22" Both A/C 300H
2276825 1963 A 19" 225 Manual Heater
2276837 1963 B 318 Manual Heater
2276838 1963 B 318 Auto Heater
2276839 1963 B 318 Both HI ALT-A/C
2276842 1963 B 22" 361 426W Both HI ALT-A/C D-P
2276842 1963 B 22" 383 Both HI ALT-A/C D-P
2276844 1963 B 22" 383 Both Heater
2276844 1963 B 22" Both Max Wedge
2276847 1963 C 22" 361 383 Both HI ALT A3, CI-2
2276848 1963 C 22" 361 383 Both A/C A3, CI-2
2276849 1963 C 22" 361 383 Both Heater A3, C1-2
2276851 1963 C 22" 413 Both HI ALT C1-2-3
2276852 1963 C 22" 413 Both A/C CI-2-3
2276853 1963 C 22" 413 Both Heater C1-2-3
2276854 1963 D 22" 413 Auto Heater Y1
2276855 1963 C 22" 413 Both HI ALT-A/C YS
2445615 1964 A 19" 170 Manual Heater
2445630 1964 B 22" 318 Manual D-P
2445631 1964 B 22" 318 Auto D-P
2445633 1964 B 22" 316 Both HI ALT-A/C D-P
2445635 1964 B 22" 361 383426 Both EXC
2445635 1964 B 22" Both All DPCD Max Wedge
2445635 1964 B 22" Both All DPCD HEMI
2445637 1964 B 22" 361 383426 Both HI ALT-A/C
2445642 1964 B 22" 361 383 Both HI ALT-A/C
2445643 1964 C 22" 413 Both HI ALT-A/C A3 6 C123
2445644 1964 D 22" 413 Auto EXC
2445645 1964 D 22" 413 Auto HI ALT-A/C
2445646 1964 C 22" 361 383 Both EXC
2445647 1964 C 22" 413 Both EXC A3 6 C123
2445656 1964 A 273 Both EXC
2524751 1964 A 273 Both HI ALT-A/C
2524952 1965 A 170 Manual Heater
2524954 1965 A 170 Auto Heater
2524956 1965 A 225 Auto Heater
2524961 1965 A 273 Both Heater
2524962 1965 A 273 Both HI ALT-A/C
2524963 1965 B 225 Manual Heater
2524966 1965 B 273 318 Manual Heater
2524968 1965 B 273 318 Auto Heater
2524969 1965 B 273 318 Both HI ALT-A/C
2524970 1965 B 22" 361 383426 Manual EXC
2524972 1965 B 22" 361 383426 Both All P
2524972 1965 B 22" 426 Both HEMI DPCD
2524978 1965 B 22" 318 Auto Heater
2524982 1965 C 22" 383-2 Both Heater
2524983 1965 C 22" 383-4 Auto Heater
2524984 1965 C 22" 383 Both HI ALT-A/C
2524985 1965 C 22" 383 Manual Heater
2524986 1965 C 22" 413 426 Manual Heater
2524989 1965 C 22" 413 426 Auto All
2582926 1966 A 19" 170 225 Manual Heater
2582928 1966 A 19" 170 225 Auto Heater
2582929 1966 A 22" 170 225 Both A/C With CAP
2582930 1966 A 22" 273 Manual Heater
2582931 1966 A 22" 273 Both Heater
2582933 1966 A 22" 273 Both HI ALT-A/C
2582937 1966 B 22" 225 Both Heater
2582939 1966 Manual A/C
2582941 1966 B 22" 273 Both
2582941 1966 B 22" 273 318 Manual EXC
2582942 1966 8 22" 318 Auto EXC
2582943 1966 B 22" 273 318 Both HI ALT-A/C-Police
2582943 1966 B 22" 273 318 Manual HI ALT
2582944 1966 B 26" Both A/C
2582945 1966 B 22" 361 383 Manual Heater Less CAF
2582946 1966 B 22" 361 383 Auto Less CAP
2582948 1966 B 26" 361 383 Auto All With CAF
2582948 1966 B 26" 426 Hemi Both All Both CAF
2582952 1966 C 22" 318 Manual Heater
2582953 1966 C 22" 318 Auto Heater
2582955 1966 C 26" 318 Auto HI ALT-A/C
2582957 1966 C 22" 383 Auto Heater
2582959 1966 C 22" 383 Both Heater Less CAF
2582961 1966 C 22" 363 Both Heater-HI ALT Both CAF
2582962 1966 C 26" 383 Both A/C With CAF
2582963 1966 C 22" 440 Manual Heater Less CAF
2582965 1966 C 22" 440 Both Heater Less CAF
2582966 1966 C 22" 440 Both HI ALT Both CAF
2582967 1966 C 26" 440 Auto A/C Both CAF
2582970 1966 A 19" 170 225 Both HI ALT-A/C Less CAF
2582972 1966 D 26" 440 Auto All
2785929 1967 A 22" 383 Both Heater
2785931 1967 C 26" 440 Auto HI ALT-A/C
2785933 1967 C 26" 440 Auto Heater
2785934 1967 B 26" 383 440 Both HI ALT-A/C
2785934 1967 B 26" 426 Hemi Both All Both CAF
2785936 1967 B 26" 383-4 Both All Both CAF
2785938 1967 C 26" 318 Both HI ALT-A/C With CAF
2785940 1967 B 26" 273 318 Both HI ALT With 355
2785942 1967 C 26" 383 Both HI ALT-A/C
2785945 1967 C 22" 440 Auto Heater
2785946 1967 C 22" 383 Auto Heater
2785949 1967 C 26" 318 Both A/C Less CAF
2785951 1967 C 28" 440 Auto HI ALT-A/C Y
2785952 1967 C 28" 440 Auto All Y
2785953 1967 C 22" 318 Auto
2785954 1967 C 22" 318 Manual
2785955 1967 C 22" 225 Both HI ALT-A/C
2785956 1967 C 19" 225 Auto Heater
2785960 1967 B 22" 383-2 Both Heater
2785962 1967 B 26" 273 318 Both A/C
2785965 1967 B 22" 273 318 Both Heater
2785965 1967 C 22" 225 Manual Heater
2785967 1967 B 19" 225 Manual A/C
2785968 1967 B 19" 225 Auto All
2785969 1967 B 19" 225 Manual All
2785970 1967 A 22" 273 Both HI ALT-A/C With CAF
2785971 1967 A 22" 273 Both A/C Less CAF
2785973 1967 A 22" 273 Auto Heater
2785975 1967 A 22" 273 Manual Heater
2785976 1967 A 22" 170 Both All
2785978 1967 A 19" 170 225 Auto Heater
2785980 1967 A 19" 225 Manual Heater
2898021 1968 A 19" 170 225 Manual Heater
2896023 1968 A 19" 170 225 Auto Heater
2898026 1968 A 22" 340 Manual Heater
2898027 1968 A 22" 273 Auto Heater
2898028 1966 A 22" 318 340 Auto Heater
2898030 1968 A 22" 273 Both A/C
2898031 1968 A 22" 318 340 Auto A/C
2898032 1965 A 22" 318 340 Manual A/C
2898033 1968 A 22" 383 440 Both Heater
2898033 1968 A 22" 426 HEMI Both Delete S/S HEMI
2698034 1965 B 19" 225 Manual Heater
2898035 1968 B 19" 225 Both Heater
2898036 1968 B 22" 225 Auto A/C
2898037 1968 B 22" 273 318 Manual Heater
2898038 1968 B 22" 273 318 Auto Heater
2898040 1968 B 26" 273 Auto A/C
2898041 1968 S 26" 318 Auto A/C
2898043 1968 B 22" 383 Manual Heater
2898044 1968 B 22" 383-2 Auto Heater
2898045 1968 B 22" 383 440 Auto Heater
2898047 1968 B 26" 440 Manual Heater With 492
2898047 1968 B 26" 383 440 Auto A/C
2898048 1968 B 26" 383 Both Heater With 358
2898048 1968 B 26" 426 HEMI Both Heater
2898051 1968 C 19" 225 Both Heater
2898052 1968 C 22" 225 Both HI ALT-A/C
2898055 1968 C 22" 318 Both A/C
2898056 1968 C 22" 318 Both HI ALT
2898057 1968 C 22" 383 Manual Heater
2898058 1968 C 22" 383 Auto
2898060 1968 C 26" 383-2 Auto A/C
2898061 1968 C 26" 383 Auto A/C
2898062 1968 C 22" 383-2 Manual Heater
2898063 1968 C 22" 383 440 Both Heater