1980 Maxima rear control arm

I was told these were 1980 280zx rear control arms, but the bolt on disc brake bracket and deeper 4 bolt flange didn't match a 2nd pr of 280zx arms. Uses same disc and brake caliper setup as 280zx.

These have been re-drilled to 5x4.5" spacing. Uses OEM solid 10.6" disc that has also been re-drilled to 5 lug. Brake disc weighs 10.25lbs each, brake caliper & pads weigh 8.66lbs each, and bare control arm w/ hub, 5 lugs and poly bushings weighs in at 30.25lbs each.