Yes Bruce your spot on.
Funny I had trouble finding plans when I googled - lots of Russia birds thought !! -
Yes a moulding if the TWS grill is the way to go, also the front grilles are different sizes by the looks to.the G2 longer than the G1.
On second thoughts it's really a whole new engine deck if one doesn't not to lengthen the fighting compartment. Maybe a 3D printer is needed