Overflow seam leak

[spacetime]

Hello,

Just finished plumbing my new 60 rimless marineland perfecto with corner overflow and the entire seam on the overflow which connects to the back panel is leaking, badly.

Is this repairable without having to re silicone the entire thing? I'm unable to remove the drains as I've added the plumbing below.

Thanks.

 

[Reefing Madness]

I would think you'd have to resilicone the whole thing as it would be alittle tough to figure if you've gotten the seam correctly with it being in place.