resealing a 210gallon questions????

[Grimreefer89]

my main question is do i HAVE to take the top brace off to reseal it. is top less than an inch that critical, this doesnt seem critical to me but i wanna be sure before i do it. id love to hear from some one who did the same on a large tank. or just advice in general.

 

[Grimreefer89]

Heres a pic of the top brace i was refering to.

 

[Grimreefer89]

This is the spot that concerns me most