The easy kit Revell Falcon (called 1/72 but seems to be 1/80) is much smaller than the mpc. MPC is about 18 inches, and that easy kit revell is about 14, I think those mandibles would be too small. Maybe you could just cut the mpc mandibles 1 cm at the tips and reposition the small boxes located at that place. Or maybe just cut the mandibles off and reposition them by sliding them a little under the plates.
For the record: the revell master series (rebox of the fine molds) is stated to be 1/72 too and is about 17 - 17.5 inches long. Bandai PG Falcon is classified as 1/72 too and is about 19" long. With that in mind, we could say the MPC is 1/72 scale too. I think all this inconsistences are generated because there is not an agreement about "the real size" of the Falcon.