'71-'73 Dart Tail Light Housing ?s

A buddy of mine (with a '71, '72 and/or '73 Dart Swinger) wants to cut the REVERSE lamp portions of his tail light housings off and weld(?) a second set of BRAKE/TAIL lamp housings in their place. He's already scored a 2nd set of housings and BRAKE/TAIL lamp lenses and housings. Can the material used on the 1971 to 1973 Dart tail light housings be welded? I assume the lense openings (BRAKE/TAIL vs. REVERSE) in the bumpers are the same size? Will he have clearance issues (assuming he gets the spacing correct) mounting on them on the car? Plans are to parallel wire the BRAKE/TAIL wiring to each. Anyone ever try/done this? Any advice?

I did this with my 73 and all it took was to replace the backup light lenses with tail brake lenses and wire them with the brake/turns from the other lights.
71-72 and 73 all have four separate lenses, and I think 74 they went to one lense for each side and the backup built into them.

Mine are all LED but this is how they work.
Parking=just the two outer lights
Left turn=both left lights
Right turn= both right lights
Brakes=all four lights

I like it a lot since it doubles my visibility on the turns and brakes, and the LED's use about 1/4 for all four lights as the regular two lenses with incandescent bulbs.