I built all four orbiters using the Monogram kit.
Here are some photos of the orbiters Discovery and Atlantis
I fixed the rectangular panel by removing it and making a casting of the intertank stringers using Aluminite resin casting. The result is seen close up here
Painted
And the back panel The center panel on the intertank is thin styrene with the antenna from the original kit panel removed and placed on the new panel.
The other change is the LH2 cable tray that runs along the side of the two gaseous lines and LO2 feed line. The kit has it all wrong with this little part. I re