You may be able to get the decals off using some masking tape (at least it tends to pull mine up) or just do a localized repaint over the decals if necessary. No need for stripping, etc. If you have a line where the decals were after the localized repaint, then I would mask off that area, and use some 0000 steel wool to buff it until it is blended (might need more paint to get to get it blended to your statisfaction if the decals are thick), and then repaint that area again. I would then cut a half circle mask about the size of the national insignia (you should have spares having the kit and barracuda decals, correct?), and then use it to mask over the invasion stripes where the decal needs to go. Spray that area with some of the green as well, so that you don't have bleed through from different colors under the decals, and then apply your decals in the correct place.
It should be a fairly easy job, if you lived closer, I'd invite you to bring it over and we could have a go.
Doug