But also such simple things as designing the undercarriage for landing at a sink rate of 6 m/s rather than 3 m/s. The whole structure will have to be redesigned.
and the undercarriage attaching structures, new wing 2 fuselage attachements, new wings, re-engine, new props, new high lift system for wings. foldable wings. new tail fins and empennagegs. etc etc.
the list goes on and on....
after after all this you would find that the only old parts is the fueslage barrel diameter and may be the nose.
Y-7 goes on carrier = never will happen.