I hadn't considered that, but I may give it some thought. I've never really looked into building an aquarium myself before, but I can rebuild an engine, so gluing some glass together shouldn't be that hard! (Famous last words?) LolI know how your goal is to save the tank...but have you considered taking it apart and using the long panels for a plywood build?
No doubt I can do it. I would've been better off without the internet to be honest. My instinct was to replace the pane, which seemed like a simple straightforward job in my mind...and then I started reading about just patching it and started to question my own judgement. Thought I'd ask the experts here first. 20 years in the hobby and this is the first cracked tank I've ever had.My first 3 aquariums where cracked one that Ms. Poly in 7th grade science class gave me for free. Two were metal framed one was conventional. That was... uhhh 40 years ago. I repaired all of them without the assistance of the internet to guide me and all of them held water for years!
Carefully cut the seals on the cracked end panel with a sharp utility knife and do your best to remove it without breaking it. Take it to a glass place and ask for an identical piece to replace it. Clean the snot out of the adjoining panes and get all the silicon residue off. Then seal the new pane in with the high strength silicone someone on this board will tell you is the best to use. If a 12 year old can do it you can do it!