The pictured wheel showing the number stamps was made in 1977 at Motor Wheel plant # 2. Some additional numbers might be found near the valve stem.
This 15" x 6.5" Rallye Class I wheel part number is 3699461 which was used from 2/17/1976 through 1977. These wheels will fit it, but were not originally equipped on a Challenger. In 1977, they were originally equipped on a B-body Fury or Monaco, or a Charger SE.
The 1976-1977 15" x 6.5" Class I trim ring was part number 3699100. The trim rings on the pictured wheels might be that number, but could also be the earlier 3461043, Mopar Performance reissued P5153310, or possibly reproductions.
NOTE: The sizing and numbering of 15" trim rings for 6.5" and 7" Rallye Class I wheels from the mid 70s and later Chrysler re-issues is somewhat convoluted because Chrysler reused the same part numbers for different sizes and production releases.
The center caps, or domes, on the pictured wheels are the 1972-1974 version, part number 3461458. They have been refinished in a color/texture different than original.
1977 wheels were originally equipped with a similar style two-piece dome with cap, part numbers 3699312 (dome) and 3699008 (cap), which continued in use though 1978.
A similar two-piece dome with cap, part numbers 3699006 (dome) and 3699008 (cap), was used with 1975 models through 1976.