[Mr70]

As far as the BB 2 & 3 core is concerned,they aren't properly reproducing the original design used on the 69-70 Chevelles.Only the BB 4 core design is offered.
The Big Block 2 & 3 core shroud is unique,in that it has a extra vertical lip overhang on the driverside to take up the extra gap when used with that smaller core.
The 4 core shroud doesn't have this D/S lip,due to the thicker core and is the same flush all around.
Because of this,an original BB 2/3 core shroud can run up to 4X more then a repop.