With the modifications shown in the above photo,they will bolt into the 73/74 bumper. My friend put them in his 73 and he used the same bumper the car came with.

70 Charger R/T SE 472 Hemi 70 Charger R/T convertible 70 Charger R/T V Code Sixpack 69 Charger R/T SE Sunroofcar 68 Charger 383 68 Charger 318 71 Charger R/T 70 Challenger convertible 71 Challenger convertible 71 Cuda 340 09 Challenger R/T Classic