I have both the Jim Key kit and the new kit. I think the bulge they are refering to on the Jim Key kit is on the large rectangular panel on the underside that would have covered the mounting point on the ship. My kit has a slight wave in that panel.
Here are some of the differences in the two kits.
Underside- The new kit left off some very small raised panels that are on the Jim Key kit.
Lower rear panel circular detail- The new kit repeats the upper circular details on the bottom. The Jim Key kit has recessed circular detail on the bottom and the detailing is different than the top details.
Cockpit side detail- The Jim Key kit has a raised side panel detail on the inside lower wall of the cockpit. This detail is missing on the new kit.
Engine exhaust detail piece- The new kit has a small gear looking detail recessed into the center of the exhaust detail piece. This is not on the Jim Key kit.
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