Hopefully, I have some information which may help.
1) According to the 1967 (page dated 9/16/66) and 1968 (page dated 3/4/68) Electrical Assembly Manuals, the Engine Lamp mounting Bracket, socket and wiring clip that mounts with the Bracket, are the same. For some reason, the 1967 Assembly Manual notes the Bracket and socket as Engineering Part # C7ZB-15702-A and the Wiring Harness portion as C7SB-15702-B, while the 1968 Assembly Manual shows Engineering # C7ZB-15702-A for the Bracket, socket and wiring. I’m not sure why this is, unless there is a connector from the wire from the socket, to the wire that goes to the inline fuse, then to the front (hot) side of the starter solenoid. If there is a connector, then I do not have the correct assembly for mine, as mine goes directly from the socket to the inline fuse and then to the solenoid. Both the 1967 and 1968 Assembly Manuals show it this way.
2) The routing, and some of the clips used on the wire from the sockert to the inline fuse, do differ between 1967 and 1968. On the 1967, the wiring from the socket is held onto the horizontal hood reinforcing by 2 – 379485-S clips that push into holes in the reinforcing; while the 1968 uses 1-372303-S clip (rubber coated S type clip) which pushes onto the sheet metal flange of the rectangular “depression” located in the center rear of the hood. From these clips, in both the 1967 and 1968 models, the wire then goes through the access hole located at the front of the depression and toward the Driver’s side, then along the depression toward the rear of the hood, exiting in another access hole at the rear of the hood. Upon exiting the hole, there should be a “locater hole” in both 67 and 68’s, into which a wiring clip that is part of the harness, is inserted. From this locater hole, for both 67 and 68’s, the wiring follows along the shock tower to cowl brace, held on with 3 - # 379061-S clips (4 for 1968 if with Speed Control).
For 1967, the wire then goes from the front of the brace, to the inline fuse, through an existing clip located just below the Starter Solenoid, then to the front (hot) side of the solenoid.
For 1968, after leaving the front of the brace, there is an additional clip (# 380753-S) located on the front of the shock tower, that the wire goes through before going to the inline fuse, after which it follows the same route as the 67’s.
As I noted at the start, this information is based on the 1967 and 1968 Electrical Assembly Manuals, and as such, could differ from what may be found on unrestored original applications. However, it at least has some kind of documentation as to what was intended.
Bob