Should I try to modify my T5 fixtures?

[cvrle1]

Hello everyone. I have 2 old T5 fixtures that I bough years ago for my old 36 gallon tank. These units are at least 10 years old, but still work. I will be setting up a standard 120G tank (4x2x2) and was thinking about incorporating these T5s with LEDs that will be using as well. Since these are 36" long, they are a foot shorter than tank. I was thinking about ripping them open and trying to expand them to be 48' long, but not sure if I should even bother with that. I could just sell them, or re-purpose for something else, and replace with LED bars or new T5 fixture of proper length.

Which way would you go? Thanks for the help

https://i.imgur.com/KC8Qirx.jpg
https://i.imgur.com/tjbFVB9.jpg
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