Four foot X-wing (ILM tribute)

[427 Cobra]

I've really screwed up now - I cut off too much from the trailing edge (red arrow) when I made the side of the intake plenum with the sealab part. I sanded it even with the acrylic base. How do I fix this? Do I start over? Meaning, do I sand off the styrene, or attempt to glue an extremely thin strip to this in the hope that it will not deform, or come back off? Either way, this is going to take some effort, but it needs to be done. I only did one side so far, so I won't have to do this again.

FYI - this is a lot bigger than it looks in this picture = about 3" each way.

~ Cobra Chris